Should the TIU have investigated these seven matches?

Ever since Sunday night, the spectre of match-fixing has been hanging over tennis. This is possibly the sport's darkest days since the now infamous Davydenko v Vassallo Argüello match in Sopot in 2007. This match has been described in detail elsewhere, so it is not something that I will dwell on here. Instead, in this article, I want to focus on three locations - Palermo in Sicily, Sopot in Poland and arguably the most famous location in tennis - Wimbledon.

An important thing to bear in mind is that I am not actively accusing any players of fixing. Instead, I wish to present the evidence that is available as a basis for people to draw their own conclusions and for further investigation if necessary.

Wimbledon - 27th June 2006

Our story begins on the 27th June 2006 at Wimbledon. In the first round, Italy's Potito Starace is drawn to face Mikhail Youzhny. The Italian had failed to even win a set in his two previous visits to Wimbledon, while the Russian had reached the second week for the third time in five attempts in 2005. When the Betfair markets opened on this match, the prices looked perfectly normal. 

As one would expect, Mikhail Youzhny was a big favourite for the match and the market initially gave him a 54.6% chance of winning the match in straight sets, which is more or less where we would expect to find the market.

However, if we look at the last bets matched on these selections before the match starts at 11am on the 27th June, we find a very different story.

We can see that while the probability of Mikhail Youzhny actually winning the match barely changed, the chances of him winning in straight sets has moved from a 54.6% chance to an 82.6% chance - almost the same probability as his chances of winning the match. In other words, the betting markets are suggesting that if he wins the match, it is almost guaranteed to be in straight sets.

So, what caused this move? Well, we can look at the Betfair data for the Youzhny 3-0 selection:

Just to explain what this is showing. The odds column refers to the odds on the selection (this can be converted to probability by taking the reciprocal), the bets column refers to the number of bets matched at this price, the volume column refers to the amount of money matched at each odds and the last and first taken columns simply refer to what time bets at those odds were first matched and last matched.

What we can see here is that from the moment the market opened until four minutes before the match started, there was consistently money flowing into the market happy to back the 3-0 at any odds. In total, there was £290,232.06 matched at all odds between 1.83 and 1.19. Just as a comparison, on all of the other markets and selections combined, there was a grand total of £92,661.52 matched. This is a large amount for a market such as this and appears to be relatively suspicious.

Suspicious in itself, but when we add in an interesting snippet of information from the leaked documents used in the Buzzfeed investigation, we find more interesting facts:

Now, this page from the document seems to be referring to the exact match that we are looking at. It shows that there were five linked accounts based in Sicily that were responsible for the vast majority of this move. Coincidence maybe? Possible, but it is the first piece of evidence to remember.

The match happened and Mikhail Youzhny won easily in straight sets by a 6-0, 6-4, 6-1 scoreline. The grand total won in the entire market (before commission) on the 3-0 scoreline was £118,822.49.

There is no suggestion at all that Mikhail Youzhny had anything to do with any questionable betting patterns in this match

Palermo - 25th September 2006

Conveniently, the next stop in our story is the city of Palermo in Sicily, the location of those linked accounts in the previous section. The first round sees Martin Vassallo Argüello drawn to face his compatriot, Juan Pablo Guzman. Vassallo Argüello was the higher ranked of the two players and would be expected to have been the favourite for this match.

The Betfair market reflected this with the first odds matched on Juan Pablo Guzman being 2.76, although that was only for £4. The first set of odds with a reasonable amount matched were 2.3 with £173.62 matched. This implied a 43.5% chance of winning the match, which seems reasonable. This was first matched at 21:38 on the evening of 24th September, the day before the match. Twelve hours later at 09:49 on the morning of the match, the price had shortened to 1.50 (66.7% chance) and by 11:32, just less than 45 minutes before the match was scheduled to begin, the price on Guzman had reached an incredible 1.10 (90.9% chance).

By the time that the match started, the price had drifted back up to 1.36, which was the last price matched at 12:10, five minutes before the match was due to start. At this point, there had been £204,282.48 matched on Guzman to win the match.

Once the match started, there appeared to be nothing overly suspicious going on with the odds. They behaved more or less as you would have expected from the initial 1.36 starting price. For much of the match, it appeared as though Guzman would win, but in the end it was not to be.

Curiously, despite the enormous pre-match move, the match was won by Martin Vassallo Argüello, who won it 2-6, 6-3, 7-5. On the face of it, a huge gamble that failed? Maybe suspicious, but maybe not. These passages from the leaked documents are referring to this match and the pre-match price movements.

So, we have an Argentinian account that is already being monitored by the Betfair integrity team for suspicious trading causing a huge pre-match move on a match involving two Argentinian players. However, Guzman lost the match, so what was going on here?

We can see that there were four accounts that won significant amounts of money on Vassallo Argüello in this match and the Argentinian account that lost almost £120,000. What you might notice is that the account that won the largest amount of money is 'Ignazio123'. If you look back at the Potito Starace match at Wimbledon, this is the same account that was backing the 3-0 there. The other three accounts are also based in Sicily. The report concludes:

Palermo - 28th September 2006

We remain in Palermo for the second round match between Martin Vassallo Argüello and the Spaniard, Oscar Hernandez. This time, there is nothing obviously noticeable in the betting markets before the match begins. There is just £32,837.76 matched in total before the start of the match and the last price matched on the two players to win are 1.75 on Vassallo Argüello and 2.28 on Oscar Hernandez.

Oscar Hernandez raced into a 4-0 lead in the opening set. We would have expected the price on Vassallo Argüello to have drifted to roughly 3.5-4.0 by this point, possibly a fraction shorter if he were playing relatively well, but just not quite getting over the line in games. What we actually find is that the biggest price that he was matched at in the entire match was just 2.42 (41.3% chance).

For whatever reason, someone is keeping the price on Vassallo Argüello from drifting too far. The price was backed back into around 2.0 (50.0% chance) by the end of the first set, which is strange given that he was matched at 1.75 just before the start and had even been matched at 1.94 before the match began.

Martin Vassallo Argüello came back to win the match in three sets. In total, there was £569,277.78 matched on the Argentinian to win the match in-running. The most interesting part again comes from the leaked documents:

Once again, it is the Sicilian and Argentinian-based accounts that have been responsible for much of the money matched on the market.

Palermo - 29th September 2006

Once again, we remain in the heartland of Sicily for our next stop, barely 24 hours after Vassallo Argüello had come from behind to beat Oscar Hernandez. This time, it was the quarter-final match against the fourth seed, Nicolas Almagro. We can see from the first and last matched prices on Almagro that there appears to be little of any great interest here:

The Spaniard has shortened very slightly, but nothing of any real note. However, the Almagro 2-0 correct score market is somewhat different:

We can see that having opened at 1.47, the market was fairly aggressively backed right into 1.20 starting from around two hours before the start of the match, scheduled for 10:00, kicking up in the twenty minutes before the start. Again, as with the earlier Starace match, we have a situation where a player is almost the same chance to win 2-0 as he is to win the match. That means that he is basically guaranteed to win 2-0 if he wins, which simply should not be the case in any match.

Nicolas Almagro would record a straight-forward 6-2, 6-2 victory and a total of £12,643.88 was won on this market in total. Small change compared to some of the wins on other matches, but a handy sum nevertheless.

Suspicious? There are certainly questions that need to be answered. It would have been deemed as suspicious on its own, but combined with the other matches in Palermo that week, it demands a full investigation at the very least.

There is no suggestion at all that Nicolas Almagro had anything to do with any questionable betting patterns in this match

Wimbledon - 26th June 2007

Almost a year to the day after our story began, we returned to the hallowed grass courts of Wimbledon for a first round match between South Korea's Hyung Taik Lee and Argentina's Martin Vassallo Argüello. Neither player had any real history at Wimbledon - Lee had made the second round three times previously, but had never progressed further losing to Federer, Rusedski and Hewitt, although he had taken sets off the latter two. Vassallo Argüello had only appeared at Wimbledon once before, three years previously when he lost in straight sets to Chile's Fernando Gonzalez.

In the days before the match, we can see that Hyung Taik Lee is backed in slightly for the match, going from 1.26 into 1.12. At these prices, we might roughly expect 3-0 prices of 2.2 and 1.8. However, we can see in the Betfair data that this was not quite the case:

This shows that in the two days before the match, the price on Hyung Taik Lee to win 3-0 was backed all the way from 1.88 (53.2%) into an extraordinary 1.08 (92.6%). What makes this price especially bizarre is that it is actually shorter than the price on Lee to win the match itself.

To repeat that, the market was suggesting that Lee was more likely to win the match 3-0 than he was to win the match itself. As it were described elsewhere, this is analogous to a football team being more likely to win a match 2-0 than it is to win the match. In every possible way, this makes no sense whatsoever.

What makes this even more interesting is the presence of people that we have met before in this story. From the leaked documents, we find this:

The Sicilian-based accounts are once again backing a 3-0 scoreline into an absurdly short price, perfectly mimicking what had happened the previous year with Potito Starace. In total, there was £106,120.18 matched on the 3-0 scoreline that paid out a grand total of £46,099.76.

There is no suggestion at all that Hyung Taik Lee had anything to do with any questionable betting patterns in this match

Sopot - 31st July 2007

Finally our story brings us to arguably the most infamous tournament with regards to fixing allegations in tennis history. However, our first stop is the first round match between Martin Vassallo Argüello and Maximo Gonzalez.

Before the match, there was nothing suspicious in the markets. Martin Vassallo Argüello opened at 1.4, drifted out to 1.88 before shortening back into 1.54 with just under £40,000 matched on him. Once the match started, Maximo Gonzalez took an early 4-0 lead, yet the odds on Vassallo Argüello were kept at around the 1.8-1.9 mark. This continued to be the case at 6-2 after Gonzalez closed out the opening set.

Maximo Gonzalez went a break up in the second set at 2-0, yet still the odds on Vassallo Argüello refused to move from the 1.8-1.9 band. The following paragraph from the leaked documents explain what happened in a six minute period after Gonzalez took a 2-0 lead in the second set.

This is an account that we have seen before during the Vassallo Argüello match at Wimbledon. Again, it could be a coincidence, but it is getting harder and harder to believe the sheer number of coincidences needed. Four linked accounts in Northern Italy won a combined £75,881 on this match.

Sopot - 3rd August 2007

This quarter-final match came less than 24 hours after the most infamous match in fixing history - the Vassllo Argüello against Davydenko match. That match has been covered in great detail elsewhere, not least in the Buzzfeed report, so we shall move on from that. In addition, the Betfair data for that match has been removed, so we cannot follow the odds and money trail ourselves.

Instead, we move onto the quarter-final between Martin Vassallo Argüello and Albert Montanes. Once again, the pre-match markets appear perfectly normal. Once the match started, Martin Vassallo Argüello won the opening set 6-2, although the first strange signs were beginning to appear as money was matched on Vassallo Argüello at 2.06, which was a bigger price than he had been at a single break up in the opening set.

Vassallo Argüello then moved into a 6-2, 3-1 lead, yet was interestingly still only 2.06 to win the match - exactly the same price as he had been at the start of the set, despite having gone a break up in the second set. Once again, I shall let the leaked reports explain what happened next:

Yet again, it is the same Northern Italian-based accounts involved as in the first round match against Gonzalez, which also started with a 6-2 set, had a break lead in the second set and lost the match. And again, the account has picked the perfect time to stop trading the market.

Either we have found the perfect trader that can judge momentum to absolute perfection or there are questions that need to be asked.

Summary

In this article, I have looked at seven matches, using a combination of the Betfair data and the leaked documents provided by Buzzfeed. In each of the matches, it might almost be possible to write each one off as simply an unusual market. Certainly without the information that has come from the 2008 investigation, this would be much easier.

However, the presence of many of the same players and the involvement of many of the same accounts, all based in either Northern Italy or Sicily makes it far more difficult to believe that this is simply one big series of coincidences. It shows the value of a proper and thorough investigation - the form that the TIU should be carrying out.

In fact, there was not a single investigation into any of these matches opened by the newly-formed TIU, despite being provided with five folders worth of paper documentation and full electronic reports on at least six of these matches as well as at least 21 other matches.

Ultimately, maybe there would not have been enough evidence to conclude that these matches were fixed. My personal opinion is that there appears to be ample evidence to suggest that there is something very suspicious going on with these matches. The author of the report himself said that "it was really as strong as any evidence we've had." However, the fact that not one of these matches was even investigated is frankly ridiculous and suggests major problems with the TIU.

Notes

1. The Betfair data is available from data.betfair.com
2. The extracts from the leaked documents are from https://www.documentcloud.org/documents/2685408-Betting-and-Telecoms.html#document/p26/a271720 that were published as part of the Buzzfeed/BBC investigation

No Evidence of Lleyton Hewitt Fixing Matches

Match fixing has been the talk of the tennis world in the past couple of days, ever since the joint Buzzfeed and BBC reports were published late on Sunday night on the eve of the Australian Open. Buzzfeed also made their data available to the public, albeit with the player names replaced by 64 digit codes. Despite this, it took me less than 6 hours to decode the 15 players that they claim "regularly lost matches in which heavily lopsided betting appeared to substantially shift the odds – a red flag for possible match-fixing."

I had been debating whether to publish this list, not wanting to do so without doing further research. I did not want to put player names out there if there were valid explanations for their matches - to me, just publishing the names without context seems rather irresponsible. However, it was not surprising when the full list was revealed this morning by @show_legend. So, now that the list is out there, here are the names:

Now, the most striking name on the list, and the one that has gained the most attention, is undoubtedly #6. Lleyton Hewitt is a former world number one and a US Open and Wimbledon champion, so any suggestion that he had been fixing matches would have been a huge story. The Buzzfeed algorithm flagged up 15 matches involved Lleyton Hewitt where there had been a significant odds movement, 13 of which Lleyton Hewitt went on to lose.

The important thing to remember is that pre-match movements in odds can be caused by any number of factors, one of which is fixing, but others also include injury concerns, players returning after a long absence or even just poor initial pricing by the bookmakers themselves.

I have randomly picked out eight of the fifteen matches that were flagged up to look at in more detail to see whether there are alternative explanations. I also enlisted the help of a professional tennis analyst, who provided predicted probabilities for some of the matches involved using a tennis model that he has created.

1. Lleyton Hewitt v Stan Wawrinka (Davis Cup 2011) - Buzzfeed Bookmaker: "B"

Opening Probability of Wawrinka winning - 43.7%
Closing Probability of Wawrinka winning - 85.5%

Quite what is going on with the Bwin odds here is rather baffling. As we can see, their prices are completely different to any of the other major bookmakers, all of which actually saw the price on Hewitt fall, suggesting that he was more likely to win the match. Really, to suggest that this match is any evidence of Hewitt fixing is bizarre and looks more like either a mistake on Oddsportal's part or on Bwin's part.

Conclusion: No evidence of anything suspicious

2. Lleyton Hewitt v Blaz Kavcic (French Open 2012) - Buzzfeed Bookmaker: "A" & "C"

Opening Probability of Kavcic winning - 48.9%
Closing Probability of Kavcic winning - 59.5%

This match at Roland Garros in 2012 was the first time that Lleyton Hewitt had been seen since the Davis Cup tie in early February, having undergone surgery to have two screws and a metal plate put into his foot in an attempt to prolong his career. Hewitt had even admitted that he had only been back on the practice courts for two weeks ahead of the French Open, so it is a match that would have been incredibly difficult for bookmakers to price up. The reality is that matches involving players coming back from injury are almost impossible to price correctly, so the fact that there is a big price move is not surprising in the slightest.

Conclusion: No evidence of anything suspicious

3. Lleyton Hewitt v Stan Wawrinka (Indian Wells 2013) - Buzzfeed Bookmaker: "D"

Opening Probability of Wawrinka winning - 67.6%
Closing Probability of Wawrinka winning - 80.0%

Another match against Stan Wawrinka shows up in this sample. This time, it followed an upset win by Lleyton Hewitt in three sets over the 15th seed, John Isner. It was a second consecutive three set victory for Hewitt in the tournament and there are possibly suggestions that he might have been fatigued or overrated after the upset win.

However, the reality is that the opening price for this bookmaker was the highest of all the six bookmakers in the sample (one bookmaker opened with a 73.5% chance for Wawrinka), while the closing price was the lowest of all the bookmakers in the sample (one closed as 75.2% chance on Wawrinka). While all the bookmakers saw a move toward Wawrinka, the others were all comfortably below the 10% move that was used as a red-flag by Buzzfeed, so likely that the bookmaker in question opened too big on Wawrinka, saw plenty of money and were forced to go short on the Swiss player to balance their book.

The calculated probability by the professional tennis analyst for this match was actually 72.5%, so right in the middle of the range of bookmaker prices, so there was nothing all that suspicious about the actual price itself.

Conclusion: No evidence of anything suspicious

4. Lleyton Hewitt v Sam Querrey (Houston 2014) - Buzzfeed Bookmaker: "A"

Opening Probability of Querrey winning - 45.5%
Closing Probability of Querrey winning - 58.1%

This match on the clay in Houston followed on from Hewitt's first ATP clay court win in almost four years in the previous round, having defeated #135 ranked Peter Polansky. Similarly to the second Wawrinka match, we find that the opening price is relatively big compared to most of the other bookmakers in the sample, while their closing price is the lowest in the sample.

The calculated probability from our tennis analyst for this match was 56.5% for Sam Querrey, so this simply looks like a match that was incorrectly priced initially and was simply correcting to a more appropriate price.

Conclusion: No evidence of anything suspicious

5. Lleyton Hewitt v Jerzy Janowicz (Wimbledon 2014) - Buzzfeed Bookmaker: "B" & "G"

Opening Probability of Janowicz winning - 46.5%
Closing Probability of Janowicz winning - 68.0%

This match had me concerned for a while. It appears as though the majority of bookmakers suspended betting on the match, while a selection of others saw a huge price move, all the way from 2.15 on Janowicz into 1.47. There appeared to be no evidence of any form of injury or anything to explain the move.

However, after digging into the Betfair history for this match, the solution revealed itself. The match was actually suspended due to rain with Janowicz leading the match at 7-5, 4-4 up and the match was not completed until the following day. As a result, a number of bookmakers re-opened their pre-match markets with revised prices on this match, which is what Oddsportal and the Buzzfeed data has picked up on. So, the price that is being compared with the opening price here is actually the price on Janowicz at a set up and on serve in the second.

Conclusion: No evidence of anything suspicious

6. Lleyton Hewitt v Benjamin Becker (Australian Open 2015) - Buzzfeed Bookmaker: "A"

Opening Probability of Becker winning - 45.5%
Closing Probability of Becker winning - 58.1%

Another example of a match where a bookmaker has initially gone up with a price that is highest in the sample and followed it up by cutting the price to one that is lowest in the sample, presumably after seeing money on Becker.

The predicted probability from the tennis analyst for this match was 53.2%, which is precisely the closing price of one of the bookmakers in the sample and very close to three others, which simply suggests that it was a market correcting itself from an incorrect initial price.

Conclusion: No evidence of anything suspicious

7. Lleyton Hewitt v Thomaz Bellucci (Miami 2015) - Buzzfeed Bookmaker: "C"

Opening Probability of Bellucci winning - 42.2%
Closing Probability of Bellucci winning - 55.9%

This was the first match that Lleyton Hewitt had played since the Australian Open, so it was naturally difficult to price. Hewitt had dominated Becker in the opening two sets before falling away physically, so over the best-of-three format, there was suggestions that he might be able to be competitive against the horribly out of form Brazilian. As it happened, the match was a horrible match to watch with the two players combining for over 120 unforced errors, but with so few matches in the run-up to this event, it is almost impossible to price it correctly to begin with.

Conclusion: No evidence of anything suspicious

8. Lleyton Hewitt v Kevin Anderson (Queens 2015) - Buzzfeed Bookmaker: "C"

Opening Probability of Anderson winning - 69.9%
Closing Probability of Anderson winning - 80.6%

This was only Lleyton Hewitt's second match in over two months, so bookmakers had little apart from previous reputation and old matches to really go on in terms of pricing this match. With Hewitt playing so sporadically in 2015, it was incredibly difficult to really grasp what level his game was at, so on his favourite surface, it could be seen as natural to lean toward giving him a chance.

The predicted probability from the tennis analyst, albeit with a large margin for error due to small sample sizes for Hewitt, was around 75.2%, so right in the range of the actual price move.

Conclusion: No evidence of anything suspicious

Final Thoughts

As we can see, of the eight matches that I have looked at, four can easily be explained by long absences before the match resulting in matches that were incredibly difficult to price with little information on Hewitt's level or condition. Two can be explained away by incorrect or questionable data, while the rest simply appear to be the price correcting itself after poor initial pricing by one individual bookmaker.

While the analysis that Buzzfeed's algorithm carried out is a good way to generate a list of players and matches to investigate in further detail, the suggestion that a player appearing on the list is a major red-flag against his name is drawing conclusions that simply cannot be drawn.

From the matches that I have looked at, there is absolutely no suggestion whatsoever that Lleyton Hewitt has been involved in fixing matches and to simply post his name among a list of players suspected of fixing without performing any further analysis or providing context is simply irresponsible. I could continue to look at more of the matches, but my suspicion is that there would be similar circumstances for the rest.

This is not to say that other names on the list may not be fixing matches, but as I have shown, without performing further analysis, that conclusion can simply not be made.

Clustering Players For Betting

Head-to-head records are an interesting topic when it comes to betting. You will often see people mention the H2h when they are presenting their case as to why a selection is value. For example, 'Player X has a 2-0 head-to-head record against Player Y, therefore they are value'. However, many other people will tend to disregard them, believing that the sample sizes are far too small to draw any meaningful conclusions.

In the majority of cases, I would agree with the latter view. Head-to-head records of just two or three matches are relatively useless in terms of trying to actually determine if there is any tactical or stylistic issues for one of the players in the match. Admittedly, H2h records such as Pennetta's 7-0 against Stosur or Tomas Berdych's 12-0 against Kevin Anderson probably do suggest there is something there, even if it is purely mental after so many consecutive defeats.

Ideally, we would be able to see the outcome if two players played against each other ten times. Or even better, fifty or one hundred or even one thousand times. However, this is clearly nothing more than a pipe dream. However, what if we could group similar players together and look at H2h records between the two groups? Might this act as a way of determining what types of players thrive against other types of players?

Can H2h records for similar players like Sara Errani and Monica Niculescu be combined?

So, the first thing to do is group players. Rather than doing it manually, which would contain inherent biases, I used a process called K-mean clustering to group every WTA player that has played at least 25 matches on hard courts over the past two seasons based on a number of statistics, including aces per service point, points won on first and second serve and points won on first and second return of serve. The 93 players were clustered into 15 groups.

The first thing to look at is whether the groups make sense. For example, if we found Serena Williams grouped with Annika Beck and Sorana Cirstea, we might conclude that the groupings are nonsense.

However, this was not the case. Looking at certain groups, we find Sara Errani, Monica Niculescu and Annika Beck forming one group, which makes sense given their weaknesses on serve and strong return games. Another group sees Coco Vandeweghe, Julia Goerges, Karolina Pliskova, Lucie Safarova, Madison Keys, Petra Kvitova and Samantha Stosur in a group that have strong serves, both first and second, but who particularly struggle returning opponent's first serves. Interestingly, I expected Serena Williams to be in a group of her own given her statistical dominance, but she is actually grouped with her sister, Venus. For those that are interested, the full list of groups is at the end of the post.

Now we are relatively content that the groups are reasonably accurate, we can start to look at how they might perform against each other. I will look at four pairings in particular, which seemed likely to throw up some interesting results.

The first is Group 12, containing Annika Beck, Monica Niculescu and Sara Errani, against Group 2, containing Coco Vandeweghe, Julia Goerges, Karolina Pliskova, Lucie Safarova, Madison Keys, Petra Kvitova and Samantha Stosur. Here, we have a group that is bottom of the averages for both points won on first and second serve, but who top the averages for first serve return points won and are close to the top of second serve return points won against top level servers, but who struggle on return (particularly first service returns).

Looking at all the matches in the past three seasons between the two groups, we find that there have been 20 completed matches. Group 12 have won 6 of them, while Group 2 have won 14. Now, given the names in Group 2, we would expect them to have won more matches. With the likes of Safarova, Kvitova, Pliskova and Stosur, who have all spent time inside the Top 10, we would have expected to see a fairly one-sided record and many of them would have been short-priced favourites.

Having said that, we find that of those 20 matches, only 10 of them were completed in straight sets, while 10 of them went the distance. Certainly with multiple short-priced favourites in these matches, the odds on the Group 12 player on the +1.5 handicap might have been rather tempting. Looking at the game handicaps, we find that the Group 12 players went 11-8-1 on the handicap. Still small samples admittedly, but it is a promising start for the Group 12 players.

Next up, let us look at Group 6 against Group 4. Group 6 includes Alize Cornet, Tsvetana Pironkova and Victoria Azarenka as a slightly unexpected trio with decent first serve stats, poor second serve, good first serve return stats and excellent second serve return stats. Group 4 contains the rather uninspiring selection of Bojana Jovanovski, Donna Vekic, Elena Vesnina, Lauren Davis, Misaki Doi, Shelby Rogers and Sorana Cirstea.

Again, we might expect Group 6 to dominate the H2h record here, particularly with the presence of former world number one, Victoria Azarenka. The results back this up - Group 6 leads the H2h against Group 4 12-3. Impressive, but with plenty of short-odds favourites, maybe nothing to shout about. However, if we look at the performance against the handicap, we find that Group 6 has gone 11-3-1 against the Pinnacle games handicap that was closest to 50-50. In other words, if you had backed the Group 6 player in all 15 matches, you would have won on the games handicap in 11 of those and got your money back in one. That is quite an impressive return.

Finally, we shall focus on Group 10, which contains Angelique Kerber, Dominika Cibulkova, Eugenie Bouchard and Li Na. Against Group 4 from earlier, this quartet is 9-5 in the H2h, but also an impressive 9-5 against the handicap with no fewer than 11 of the meetings being concluded in straight sets. Against Group 6, we find that they are an identical 9-5 H2h record and 9-5 against the handicap again.

The results are summarised below:

Group A	Group B	Matches	Won	Lost	A Covered	A Failed	Push	2 Sets	3 Sets
12	2	20	6	14	11	8	1	10	10
6	4	15	12	3	11	3	1	12	3
10	4	14	9	5	9	5	0	11	3
10	6	14	9	5	9	5	0	10	4

There are obviously many other combinations that we could look at, but merely by focusing on those four combinations, we find that they would have gone 40-21-2 against the closest Pinnacle line to 50-50 on the games handicap or a 63.5% winning record. By grouping players by the most basic of stats, we can find certain types of player that thrive against other particular types of players, which could give us an advantage in the future.



Summary of Groups

Group 1
Agnieszka Radwanska, Ana Ivanovic, Camila Giorgi, Caroline Wozniacki, Ekaterina Makarova, Garbine Muguruza, Jelena Jankovic, Maria Sharapova and Simona Halep

Group 2
Coco Vandeweghe, Julia Goerges, Karolina Pliskova, Lucie Safarova, Madison Keys, Petra Kvitova and Samantha Stosur

Group 3
Alexandra Dulgheru, Alison Riske, Jana Cepelova, Kiki Bertens, Kimiko Date Krumm, Shahar Peer

Group 4
Bojana Jovanovski, Donna Vekic, Elena Vesnina, Lauren Davis, Misaki Doi, Shelby Rogers and Sorana Cirstea

Group 5
Alison van Uytvanck, Caroline Garcia, Irina-Camelia Begu, Magdalena Rybarikova, Polona Hercog and Silvia Soler-Espinosa

Group 6
Alize Cornet, Tsvetana Pironkova and Victoria Azarenka

Group 7
Serena Williams and Venus Williams

Group 8
Ajla Tomljanovic, Anastasia Pavlyuchenkova, Francesca Schiavone, Jarmila Wolfe, Kaia Kanepi, Kristina Mladenovic, Marina Erakovic, Mirjana Lucic-Baroni, Mona Barthel, Monica Puig and Sabine Lisicki

Group 9
Andrea Petkovic, Carla Suarez Navarro, Johanna Larsson, Kurumi Nara, Saisai Zheng, Timea Bacsinszky and Varvara Lepchenko

Group 10
Angelique Kerber, Dominika Cibulkova, Eugenie Bouchard and Li Na

Group 11
Anna Schmiedlova, Klara Koukalova, Shuai Zhang, Urszula Radwanska and Zarina Diyas

Group 12
Annika Beck, Monica Niculescu and Sara Errani

Group 13
Barbora Zahlavova, Daria Gavrilova, Lesia Tsurenko and Madison Brengle

Group 14
Belinda Bencic, Casey Dellacqua, Elina Svitolina, Flavia Pennetta, Roberta Vinci, Shuai Peng, Sloane Stephens and Svetlana Kuznetsova

Group 15
Bethanie Mattek-Sands, Christina McHale, Daniela Hantuchova, Heather Watson, Karin Knapp, Katerina Siniakova, Kirsten Flipkens, Stefanie Voegele, Vera Zvonareva, Yanina Wickmayer and Yaroslava Shvedova

WTA '10 To Watch' - 2016 Edition

Following on from the 2014 and 2015 editions (which you can view here and here respectively), the latest edition of the 'Players to Watch' is now up and running. This year, the list has been reduced to ten players, rather than twenty, but the idea remains the same. It will focus on ten of the most promising teenagers in the women's game and follow their progress throughout the year. The only criteria is that the players must be below the age of 20.

There are a selection of teenage players at different stages of their development, but all of whom have the potential to really push on in 2016, whether that be establishing themselves inside the top 100 and on the WTA Tour, making an impact at the ITF level in their first full season at that level or becoming a force in the junior game. However, whatever their aims for 2016, all of the players have the potential to reach the upper levels of the women's game in the coming decade.

1. Darya Kasatkina

Basic Information
Age: 18 (07 May 1997)
Nationality: Russia
World Ranking: 75

2015 Record
WTA: 7-5
WTA Qualifying: 11-2
ITF: 35-8 (5 Titles)
Juniors: 0-0

Career Highlights

Former Junior #3. Junior French Open champion in 2014. Seven ITF titles so far, including five $25k and one $50k events. First WTA main draw win against Aleksandra Krunic in Bad Gastein in 2015, where she made the quarter-final. First WTA semi-final in Moscow last year. Reached the third round in her debut Grand Slam event at the US Open in 2015.

2. Ana Konjuh

Basic Information
Age: 18 (27 December 1997)
Nationality: Croatia
World Ranking: 82

2015 Record
WTA: 11-9 (1 Title)
WTA Qualifying: 12-8
ITF: 0-0
Juniors: 0-0

Career Highlights

Former Junior #1. Junior Australian and US Open champion in 2013. Three further Grade 1 junior titles, plus Grade A junior title at Orange Bowl in 2012. First career WTA win in Auckland 2014 beating Roberta Vinci in three sets. 17 victories over top 100 ranked opponents. First career WTA title in Nottingham in 2015.

3. Marketa Vondrousova

Basic Information
Age: 16 (28 June 1999)
Nationality: Czech Republic
World Ranking: 399

2015 Record
WTA: 0-0
WTA Qualifying: 0-0
ITF: 17-5 (1 Title)
Juniors: 32-7

Career Highlights

Current Junior #2. Won Grade A Trofeo Bonfiglio in 2015 and Junior Fed Cup. Has reached three junior Grand Slam semi-finals at French Open (twice) and Wimbledon. Beaten finalist in first ever senior ITF event in Sharm El Sheikh. First ITF title in her third event at Zielona Gora. Recorded victories over Andrea Hlavackova and Ons Jabeur to reach final round of qualifying for WTA event in Prague.

4. Sofya Zhuk

Basic Information
Age: 16 (01 December 1999)
Nationality: Russia
World Ranking: N/A

2015 Record
WTA: 0-0
WTA Qualifying: 0-0
ITF: 3-1
Juniors: 14-7

Career Highlights

Former Junior #4. Junior Wimbledon champion in 2015 without dropping a set. Three further Grade 1 junior titles in 2014. Won the title in her second ever ITF tournament in Shymkent at the age of only 14 in 2014 without dropping a set. Graduate of Justine Henin's tennis academy in Belgium.

5. Anastasia Potapova

Basic Information
Age: 14 (30 March 2001)
Nationality: Russia
World Ranking: N/A

2015 Record
WTA: 0-0
WTA Qualifying: 0-0
ITF: 0-1
Juniors: 36-10

Career Highlights

Current Junior #18. Formerly Tennis Europe U14 #1 and Les Petit As champion. Current Tennis Europe #6 ranked junior. US Open junior doubles finalist in 2015 and Wimbledon singles quarter-finalist. Back-to-back semi-finals in Grade 1 Yucatan Cup and Grade A Orange Bowl to finish 2015 season. Took a set off former world #20, Alisa Kleybanova, in her first ever ITF senior main draw match.

6. Amanda Anisimova

Basic Information
Age: 14 (31 August 2001)
Nationality: United States
World Ranking: N/A

2015 Record
WTA: 0-0
WTA Qualifying: 0-0
ITF: 0-0
Juniors: 17-7

Career Highlights

Current Junior #40. Won junior Grade A title at Abierto Juvenil Mexicano in November 2015 beating several top 10 ranked junior players. Backed it up with a run to semi-finals of Eddie Herr International. Top ranked American player in her year by TennisRecruiting.

7. Ivana Jorovic

Basic Information
Age: 18 (03 May 1997)
Nationality: Serbia
World Ranking: 190

2015 Record
WTA: 0-0
WTA Qualifying: 0-1
ITF: 25-11 (3 Titles)
Juniors: 0-0

Career Highlights

Former Junior #1. Junior French Open finalist in 2014. Won Grade A title in Osaka and reached final of Grade A Orange Bowl in 2013. Won first ITF title in 2012 at Sharm El Sheikh. Won first $50k title in New Delhi in 2014 and added three further ITF titles in 2015, including second $50k title in Ankara. First top 100 victory in 2015, beating Vitalia Diatchenko in St. Petersburg.

8. Bianca Vanessa Andreescu

Basic Information
Age: 15 (16 June 2000)
Nationality: Canada
World Ranking: 644

2015 Record
WTA: 0-0
WTA Qualifying: 0-1
ITF: 4-2
Juniors: 43-11

Career Highlights

Current Junior #4. Won Grade A title at Orange Bowl in 2015 to add to Grade 1 title at Canadian Open earlier in the year. Helped Canada to semi-final of junior Fed Cup, winning all of her singles matches. Reached the final in her first senior ITF event in Gatineau, beating three top 300 players in straight sets.

9. Dalma Galfi

Basic Information
Age: 17 (13 August 1998)
Nationality: Hungary
World Ranking: 334

2015 Record
WTA: 0-0
WTA Qualifying: 0-0
ITF: 22-5 (3 Titles)
Juniors: 32-8

Career Highlights

Current Junior #1. Won the junior US Open title in 2015 dropping just a single set. Also won Grade A title at Abierto Juvenil Mexicano in 2014 and two Grade 1 titles at Roehampton and Eddie Herr. Two ITF titles in 2014 and added a further three in 2015, including first $25k title in Cairns, where she picked up her first top 300 victory.

10. CiCi Bellis

Basic Information
Age: 16 (08 April 1999)
Nationality: United States
World Ranking: 234

2015 Record
WTA: 2-2
WTA Qualifying: 2-3
ITF: 10-6 (1 Title)
Juniors: 4-1

Career Highlights

Former Junior #1. Grade 1 titles at Easter Bowl and International Spring Championships, plus Grade A title at Trofeo Bonfiglio in 2014. Beat Dominika Cibulkova at the 2014 US Open to record her first ever WTA and Grand Slam victory. Won two ITF titles in 2014 and added a third title in 2015 at Rancho Santa Fe. Reached third round in Miami, beating 29th seed Zarina Diyas before losing to Serena Williams.