Category Archives: Wimbledon

Margin of Error Podcast: Episode 22

A new podcast is out!

With Wimbledon in the books, Amy and I take you through the fortnight’s winners, losers, and inexplicable sleeve-wearers.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

Leave a comment

Filed under Margin of Error podcast, Wimbledon

Nick Kyrgios and the First Fifty Matches

When Nick Kyrgios lost the Wimbledon quarterfinal to Milos Raonic yesterday, he was playing his 50th career match at the Challenger level or above. Round numbers invite big-picture analysis, so let’s see how Kyrgios stacks up to the competition at this early milestone.

When Monday’s rankings are released, Nick will debut in the top 100, all way up to #66. Only Rafael Nadal (61), Gael Monfils (65), and Lleyton Hewitt (65) have been ranked higher at the time of their 51th Challenger-or-higher match.  Roger Federer was #93, Novak Djokovic was #128, and Jo Wilfried Tsonga was #314. Of the current top 100, only ten players reached a double-digit ranking by their 51st match.

The wealth of ranking points available at Grand Slams have played a big part in Kyrgios’s rise, but they don’t tell the whole story. He has won 36 of his first 50 matches, equal to the best of today’s top 100. Nadal went 36-14, and next on the list is Djokovic and Santiago Giraldo (who played almost all Challengers) at 34-16. Most of Nick’s wins before this week came at Challengers, and he has won four titles at the level.

No other active player won four Challenger titles in his first 50 matches. Eight others, including Djokovic, Tsonga, Stanislas Wawrinka, and David Ferrer, won three. All of them needed more events at the level to win three titles than Kyrgios did to win four.

Nick’s short Challenger career is another indicator of a bright future. He has only played nine Challenger events, and with his ranking in the 60s, he may never have to play one again. As I’ve previously written, the best players tend to race through this level: Federer, Nadal, and Djokovic all played between eight and twelve Challengers. It’s a rare prospect that makes the jump in fewer than 20 events, and when I researched that post two years ago, more than half of the top 100 had played at least 50 Challengers.

One category in which the Australian doesn’t particularly stand out is age. When he plays his 51st match, he’ll a couple of months past his 19th birthday. Roughly one-quarter of the current top 100 reached that match total at an earlier age. Nadal, Richard Gasquet, and Juan Martin del Potro did so before their 18th birthday, while Djokovic, Hewitt, and Bernard Tomic needed only a few more weeks beyond that.

Without knowing how Kyrgios would’ve performed on tour a year or two earlier, it’s tough to draw any conclusions. His 36-14 record at 19 certainly isn’t as impressive as Rafa’s equivalent record at 17.

Cracking the top 100 at 17 or 18 is a much better predictor of future greatness than doing so at 19, but as the tour ages, 19 may be the new 16. Grigor Dimitrov didn’t enter the top 100 until he was three months short of his 20th birthday, while Dominic Thiem and Jiri Vesely were still outside the top 100 on their 20th birthdays. Among his immediate cohort, Kyrgios stands alone: No other teenager is ranked within the top 240.

As predictive measures go, Nick’s Wimbledon performance–built on his poise under pressure–is the best sign of them all. Only seven active players have reached a Grand Slam quarterfinal as a teenager, and four of them–Fed, Rafa, Novak, and Lleyton–went on to reach #1. (The other three are Delpo, Tomic, and Ernests Gulbis.)

For a player with only fifty matches under his belt, that’s excellent company.

5 Comments

Filed under Aging trends, Challengers, Nick Kyrgios, Wimbledon

Nick Kyrgios, Young Jedi of the Tiebreak

At Wimbledon this year, 19-year-old rising star Nick Kyrgios has shown himself to be impervious to pressure. In his second round upset of Richard Gasquet, he tied a Grand Slam record by surviving nine match points. Against Rafael Nadal, he withstood perhaps the best clutch player in the game. Despite Nadal’s stature as one of the best tiebreak players in the game, the Australian won both of the tiebreaks they contested.

As I’ve shown in other posts, tiebreaks are–for most players–toss-ups. Better players typically win more than 50% of the tiebreaks they play, but that’s because they’re better players, not because they have some tiebreak-specific skill. Only a very few men–Nadal, Roger Federer, and John Isner are virtually alone among active players–win even more tiebreaks than their non-tiebreak performance would indicate.

Kyrgios is making a very strong case that he should be added to the list. In his career at the ATP, ATP qualifying, and Challenger levels, he’s won 23 of 31 tiebreaks, good for an otherworldly 74% winning percentage. Isner has never posted a single-season mark that high, and Federer has only done so twice.

Nick isn’t playing these matches against weaker opponents, and he isn’t cleaning up in non-tiebreak sets. (Too many scores like 7-6 6-1 might suggest that he shouldn’t have gotten himself to 6-6 in the first place.) Based on Kyrgios’s serve and return points won throughout each match, a tennis-playing robot would have had a 52% chance of winning each tiebreak.

Given those numbers, it’s extremely likely that Kyrgios is one of the outliers, a player who wins many more tiebreaks than expected. There’s only a 1% chance that his excellent winning percentage is purely luck. We can be 95% sure that a tiebreak winning percentage of 58% or better is explained by skill, and 90% sure that his tiebreak skill deserves at least a winning percentage of 62%.

Either one of these more modest figures would still be excellent. Milos Raonic, his quarterfinal opponent and a player who represents an optimistic career path for Kyrgios’s next few years, has posted a 58% tiebreak winning percentage at tour level. Tomorrow’s match won’t be enough to prove which player is better in these high-pressure moments, but given each man’s playing style, it’s almost certain that we’ll see Kyrgios tested in another batch of tiebreaks.

Leave a comment

Filed under Nick Kyrgios, Tiebreaks, Wimbledon

Unbroken Grand Slam Quarterfinalists

Through the first four rounds at Wimbledon, Roger Federer‘s serve has not been broken. In that span, he has faced nine break points, including only four in his last three matches.

Since 1991–the first year for which match stats are available–this is only the 8th time a player reached the quarters of a men’s major without losing serve. Only Federer in 2004 and Ivo Karlovic in 2009 have done so at Wimbledon. Federer and Nadal are the only players to have done so more than once. (Fed was also unbroken through four matches in Melbourne last year, and Rafa accomplished the feat  at the 2010 and 2013 US Opens.)

Roger’s nine break points faced are a bit less impressive. More than 5% of the 752 Grand Slam quarterfinalists since 1991 have allowed fewer, including Federer himself on several occasions. He allowed only three break points at Wimbledon in 2007, and only four at three other majors.

Dominant as such a performance is, it’s less clear whether it has any predictive value. A major confounding factor is quality of competition–would anyone expect Paolo Lorenzi or Santiago Giraldo to break Federer on grass? While he built on these superb serving performances and went on to win the title at Wimbledon in 2004 and 2007, he failed to do so at the three majors when he allowed only four break points through this stage of the tournament.

Without accounting for player quality, there is a weak negative correlation between matches won at the event and break points (and breaks) allowed. (For instance, for matches won and break points allowed in the first four matches, r = -0.25. Excluding Roland Garros, r = -0.27.) In other words, if all you know about two players is how many break points they faced in the first four rounds, bet on the guy who faced fewer.

But it’s a weak relationship, and when player quality is taken into account, it vanishes to almost nothing. Eight of the 24 players who were broken one or fewer times in the first four rounds went on to win the title, but I suspect that has more to do with the prevalence of Rafa, Roger, and Pete Sampras–the best players are most likely to go unbroken, and the best players are most likely to go deepest at Slams.

When the best players struggle on serve in early rounds, it’s hardly a death knell for their title chances. Only four times in Fed’s 31 previous hard- and grass-court Slam quarterfinal runs has he been broken more than six times before the quarters, and he won the tournament one two of those four occasions. He’s surely happy to be into the quarterfinals this week with a minimum of fuss, but the fuss level only says so much about how happy he’ll be come Sunday.

Leave a comment

Filed under Roger Federer, Wimbledon

Margin of Error Podcast: Episode 21

A new podcast is out!

Amy and I have plenty to say about the final 16 (or 18, or 19) men and women at Wimbledon. We take you through the first week’s upsets, marathons, and controversies, and look ahead to how the final rounds will play out.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

Leave a comment

Filed under Margin of Error podcast, Wimbledon

Margin of Error Podcast: Episode Twenty with Carl Bialik

Our Wimbledon preview podcast is out!

With Wimbledon only hours away, Amy and I are joined by FiveThirtyEight.com’s Carl Bialik as we preview the upcoming Grand Slam.

You can find the podcast and subscribe with iTunes here. For other subscription methods, here’s an XML feed. Otherwise, keep an eye out for a new episode early each week, which I’ll post here on the blog.

Click here to listen.

Leave a comment

Filed under Margin of Error podcast, Wimbledon

Teenagers, Thirty-Somethings, and Americans at Grand Slams

I’ve put together a few reports showing how age distributions and US presence have changed over the years at Grand Slams.  Let’s start with player age.

The average age of players in the Wimbledon men’s singles draw is 27.7 years, which is just short of the all-time record, 27.8, set at Roland Garros last month, and equal to last year’s figure at Wimbledon. There are two teens in the draw (up one from last year), and 34 thirty-somethings, which is tied for third-most since 1982.

This report shows the complete year-by-year breakdown for the last 30 years’ worth of men’s slam draws.

The average age in the Wimbledon women’s draw is also very high by historical standards.  At 25.2 years, it’s tied with this year’s French Open and 2012 Wimbledon for the highest ever.  43-year-old Kimiko Date Krumm moves the needle all by herself; without her, the average would be 25.0, still considerably higher than any other pre-2010 slam.

There are ten teenagers in the draw, which is very low for the WTA, but safely above the all-time low of 7, set at Wimbledon two years ago. The total of 16 players aged 30 or over is good for third-most of all time, behind this year’s and last year’s French Opens.

Here’s the WTA report showing these numbers for each slam in the last 30 years.

(All of the figures above for 2014 Wimbledon could change slightly if more lucky losers are added to the draw.)

I also put together a couple of reports showing the number of Americans in each slam draw, broken down by direct entrants, qualifiers, lucky losers, and wild cards, along with the top seed, the number of seeds (and top 16 seeds), plus the number of Americans in each round:

Enjoy!

 

Leave a comment

Filed under Aging trends, American tennis, Grand Slams, Wimbledon

How Underdogs Could Win Wimbledon Doubles

Yesterday, wildcards Jonathan Marray and Frederick Nielsen won the Wimbledon doubles title.  Nobody saw that one coming–in recent years, men’s doubles has been dominated by a small number of specialists.  When a team outside the top 10 wins an event, it’s often thanks to a top singles player or two.  Marray and Nielsen sit comfortably outside either category.

How did they do it?  Obviously, they played great tennis, winning big point after big point against some of the best doubles teams in the world.  (They played a fifth set three times in the tournament, but the Bryan brothers could only take them to four!)  Beyond that, there are structural elements making it possible: Men’s doubles has steadily become more equal, as better equipment and training have leveled the playing field.  The event is underdog-friendly, and it is particularly so at Wimbledon.

Hold machines

In most men’s doubles matches, breaks of serve are as rare as in a John Isner fifth set.  In yesterday’s final, the server won 73% of all points.  Mathematically, that translates to a hold rate of 93%, or one break every 14 games–less than one per set.  (In fact, it was even lower than that: three breaks in 53 standard games: 1 per 17.7.)

First serve percentages are even more remarkable.  Yesterday, both teams won 80% of first serve points.  In the two semfinals, more than 80% of first serve points resulted in wins for the server, and the Bryans won 85% of their first offerings.  For comparison, consider that on grass, Roger Federer’s career first serve winning percentage is 78.6%.  You get the picture: service breaks are very hard to come by.

When there are so few service breaks, sets (and by extension, matches) can hinge on a very small number of points.  Marray/Nielsen played 27 sets in the tournament, and 13 were decided in a tiebreak.  Of those 13, 11 were 7-4 or closer.  The wildcard champions squeaked through five of their six matches.

A few good points

Men’s doubles is dominated by the serve, and when the surface favors servers even more, matches–even best-of-five matches–hinge on just a few important points.  Consider Marray/Nielsen’s third-round upset of Qureshi/Rojer: 7-6(5) 7-6(4) 6-7(4) 5-7 7-5.  Essentially, 56 games–every game to the first three tiebreaks, and then to 5-5 in the final two sets–had no purpose other than wearing down the other side.  If only one or two points had gone differently in the first two sets, the AntiPak express would have won the match in the fourth set, and the Bryans would probably be lifting the trophy as usual.

This isn’t to lessen Marray/Nielsen’s achievement–far from it.  Fast-court doubles has been reduced to a thirty-point contest, and the underdog duo won all five of those mini-matches in which they found themselves.  The other 250 points function simply to prove that both teams belong there.  And any team that can win 70-75% of service points has a good chance of proving themselves.

Once you’ve reduced the match to 30 points, luck–and mental fortitude–play a bigger role.  If you’re playing Novak Djokovic on the singles court, you can be as mentally strong as you want, but if you don’t have top-ten skills, you’re going to lose.  In doubles, steely nerves at 4-4 in a breaker, maybe with a couple of lucky netcords or reflex volleys thrown in, can be enough.

While there is certainly some skill that separates the Bryan brothers from the Ratiwatana brothers, even the journeymen Thais pushed Lindstedt and Tecau to tiebreaks in two of their three first-round sets.  I hesitate to use the word “clutch,” but on Centre Court, with a hundred thousand pounds on the line, tiebreaks are about more than serves and volleys.  What the wildcards proved over the fortnight is that, at least for two weeks, they possessed the rarest of modern doubles skills: They could play the big points with the big boys.

Leave a comment

Filed under Doubles, Wimbledon

The Misleading Stat Sheet

A glance at the stat sheet from Serena Williams’s third-round match against Jie Zheng suggests that Serena dominated.  23 aces to 1, 3 break point conversions to none, 54 winners to 21, 84% 2nd-serve points won to 50%, and 55% of the total points played.

Of course, according to the more important stats–games and sets–Serena didn’t dominate.  She barely snuck through, losing a first-set tiebreak and going to 9-7 in the third.

Rick Devereaux, who brought this contrast to my attention, suggests that grass-court tennis–with more clean winners and fewer unforced errors than slower-paced styles–may be responsible.  That’s certainly part of the equation.

In fact, the Serena/Zheng match highlights the limits of the traditional stat sheet, especially on a surface that particularly favors the server.  Except for winners and unforced errors, nearly every stat directly captures some aspect of serving prowess–either yours or your opponent’s.  And in an era where nearly everyone is an excellent server, it doesn’t matter much whether you’ve set down a great serving performance or merely a good one.

To get to tiebreaks (or 9-7, or 70-68), you don’t have to be as good as your opponent, you just need to be good enough to hold.  Even the “winners” stat has to do with serving dominance, since so many are third shots behind a serve.  The vast majority of the stats from Serena’s match tell us that the American was more dominant on her serve than Zheng was.  And, of course, while Zheng was good enough to hold to 6-6 and 7-7, she lost the second set fairly badly, so the stats are a weighted average of two almost-even sets and one lopsided one.

When we find a mismatch between stat sheet and scoreline, we’re usually seeing one of two things:

  1. One player was much more dominant on serve (think 4 or 5-point games instead of 6+)
  2. One player won a lot of clutch points (like deuce, on serve) — losing unimportant ones (like 40-0 on serve), thus padding her opponent’s stat sheet.

Oddly, in the men’s game, the players who we think of as most dominant on serve rarely give us mismatched score sheets like this–quite the opposite.  Note the wording: “one player was much more dominant.”  There’s no doubt John Isner can dominate on serve, but since almost all his opponents are also good servers, Isner’s weak return game means that he is often the less dominant server, winning service games at 40-30 and losing return games at 0-40 or 15-40.  In fact, Isner has won more than 20 career matches despite losing more than half of the points played!

The same reasoning doesn’t apply to Serena.  She may be as big a server (relative to her opponents) as Isner, but her return game is also world-class.  And in the WTA, there are far more weak-to-middling servers.  On grass, as Rick points out, those weak-to-middling servers are (usually) still able to hold, making it more likely that a dominant performance on paper ends at 9-7 in a deciding set.

5 Comments

Filed under Oddities, Wimbledon, WTA

The Greatest Upset in Sports Recency

Last night, Lukas Rosol shocked the tennis world by beating Rafael Nadal.  Immediately, the verdict was in: One of the greatest (the greatest?) upsets of all time.  Completely unthinkable.  Impossible to see coming.

And to a certain extent, that’s correct.  Nobody picked Rosol to beat Nadal; I’d be surprised if anyone went on the record forecasting that the Czech would win a single set.  But for all that, the superlatives have gone too far.  It’s one thing to predict that Djokovic/Nadal/Federer/whoever will win a certain match.  It’s another to make the broader claim that they will always beat opponents of a certain level.  The first claim is a sound one; the second is madness.

One way to look at this is a glance at the betting market.  For high-profile matches, punters and sportsbooks give us a good idea of the conventional wisdom going into a match.  Pre-match odds varied from (very roughly) 25:1 to 75:1.  Even if we go to an extreme and take odds of 100:1, that means that the market gave Rosol a 1% chance of victory.  A small chance, but far from a zero chance.

So, of course, Nadal should have gotten through to the third round–he probably should have gotten to the semifinals.  But with 1% underdogs at every step, every once in a while it’s not going to happen.  Consider that each of the top three play two matches against unseeded opponents at every slam.  That’s six opportunities at every slam for a greatest upset of all time.  The occasional first- or second-rounder doesn’t fit the bill, like Nadal-Isner at last year’s French, but later-round matches take their place, like Federer-Goffin last month.

Given 24 opportunities per year, there should be one such upset every four years.  That’s still newsworthy, but statistically speaking, it’s not the greatest upset in tennis history, it’s the greatest upset in very recent memory.  And that’s just counting slams.

No nobody

Part of the reason we overreact to these things is that our brains aren’t wired to think about small probabilities–it’s either likely or it’s not.  Another reason is the historically unprecedented dominance of the big three.

Contributing to the effect is something that Steve at Shank Tennis pointed out:  The media is inaccurately portraying Rosol as a “nobody.”  Sure, Rosol has never played a Wimbledon main draw before, and he’s beaten a top-20 opponent only once. But this is the third-ranked player from the Czech Republic, a man who has been in the top 101 for more than a year, peaking inside the top 70.  In any major team sport, a top-100 player is among the top five on his team; number 65 might make an all-star team.

When Donald Young beat Andy Murray, we were shocked, but not to the same extent–we all know about Young’s potential, and besides, American fans have been talking about him for years.  Even when Alex Bogomolov registered the same upset the following week, it was a recognizable name, also in part due to US wild cards and press attention.

Rather than dismissing yesterday’s match as a freak event involving a player who we’ll never hear from again, we’re better off to treat it as a sign of just how strong the back of the field is.  Rosol is not the only man outside of the top 50 with a thunderous game.  He’s not the only threat on tour who was never talked up as a junior.  And he’s certainly not going to be the last “journeyman” to register a high-profile upset over an “unbeatable” opponent.

7 Comments

Filed under Rafael Nadal, Wimbledon