Novak Djokovic’s Amazing, Challenging Season End

You’ve probably heard the stats by now.  Novak Djokovic ended the 2013 season on a 24-match winning streak.  13 of his last 20 matches–all wins, of course–came against fellow members of the top ten.

Carl Bialik argues that Djokovic’s latest exploits, taken as part of his career as a whole, force us to consider him as an all-time great, in line with the seven other players who have won six to eight Grand Slam titles.  It’s a convincing case.  While Novak remains well behind Roger Federer and Rafael Nadal in most of the usual GOAT-debate categories, those are some awfully high standards to meet.  In any other era, he wouldn’t be burdened with such impossible comparisons.

Djokovic’s season-ending streak is notable in itself.  Since 1983, only three other players have won 13 or more consecutive matches against members of the top ten: Federer (24, starting at the end of 2003, among other streaks), John McEnroe (15, in early 1984), and Nadal (13, from 2012 Monte Carlo to 2013 Monte Carlo).

Djokovic’s status among the all-time greats gets a boost when you realize that this isn’t his first such streak. Coinciding with the streak, Novak won 13 consecutive contests against top-ten players in the first five months of 2011.

What makes his most recent run all the more impressive is that he has done it with so few pauses for breath.  11 of his last 14 matches were against top tenners, as were 13 of his last 19.  By contrast, Nadal’s otherwise comparable top-ten winning streak spread over 50 matches.

In fact, the tail end of Novak’s 2013 season was one of the most challenging on record.  Since 1983, only seven men played more than half of a 20-match span against top-tenners.  Federer, Nadal, and Djokovic head the list, as usual; the others are McEnroe, Andre Agassi, Pete Sampras, and Nikolay Davydenko.  Aside from Djokovic this fall, Agassi is the only one of the seven who has played 13 or more top-ten opponents in a 20-match span.  And unlike Novak, Agassi wasn’t perfect.  In his demanding stretch at the end of 1994, he lost to Goran Ivanisevic in Stockholm and to Sampras in the semis of the Tour Finals.

The nature of Djokovic’s season-ending winning streak emphasizes his stature among the sport’s greats.  In an era when a handful of contenders so thoroughly dominate the rest of the field, that small group of players is constantly facing one another.  While I don’t envy anyone playing the likes of Ivanisevic indoors, even that fearsome thought pales next to the Nadal-led gauntlet that Novak has spent the last three months navigating.

The Questionable Wisdom of the Drop Shot

Italian translation at settesei.it

More than any other shot in tennis, the drop shot can make the player who hits it look either brilliant or idiotic.  The line separating the two is rarely so fine.

When we combine the brilliance and the idiocy, how does the drop shot measure up?  How much does a player gain or lose with frequent use of the dropper?

In the final match of last week’s Challenger Tour Finals between Alejandro Gonzalez and Filippo Volandri, Volandri hit a whopping 23 drop shots–almost one per game (click the “Shot Types” links).  Volandri is a seasoned pro with an excellent sense of clay court tactics, so he avoided the clunkiest drop shot misses–only three of the 23 were errors.  Yet despite facing an opponent who prefers to camp out well behind the baseline, the Italian won only 11 of the 23 points.  Almost half the time the drop shot landed in the court, Gonzalez chased it down, got a return in play, and went on to win the point.

Volandri’s performance in the final wasn’t an anomaly.  In the semifinal against Teymuraz Gabashvili, he attempted 17 drop shots and won only nine of those points.  The other aggressive drop-shotter at the CTF, Oleksandr Nedovyesov, hit 19 drop shots against Gabashvili in a round-robin match.  Even though eight of those 19 drop shots were winners, Nedovyesov lost ten of the ensuing points.

With my shot-by-shot analyses of five matches from last week’s event in Sao Paulo, we can take a somewhat broader look at drop shot tactics and their results.  While this subset may not be representative of all clay-court tennis (for one thing, the altitude makes it a bit easier to chase down a dropper), the aggregate numbers raise some questions about the wisdom of the drop-shot tactic.

As a whole, the six players who took part in these five matches hit 95 drop shots.  16 (16.8%) of them were unforced errors, compared to an overall rate of about 1 unforced error per 10 rallying shots.  29 (30.5%) were outright winners, while another five induced forced errors, immediately ending the point.  That leaves 45 points (47.4%) in which the opponent got the ball back in play.  Of those, the dropshotter won only 19 (42.2%).

Taken together, the results aren’t bad.  The player who hit the drop shot won 53 (55.8%) of the points, and 67.1% of the points when the drop shot landed in play.

There is a noticeable difference, however, in the success rates of the frequent dropshotters (Voladri and Nedovyesov) compared to those of the other four players, who averaged fewer than four drop shots per match.  While the players of what I’ll call the “infrequent group”–Gabashvili, Gonzalez, Guilherme Clezar, and Jesse Huta Galung–may not be as practiced in the art, it is likely that they chose their moments much more carefully, hitting drop shots when the tactic was obvious.

The infrequent group hit 22 drop shots, missing only two.  Not only did nine go for winners, but the overall results were positive as well, as they won 14 (63.6%) of those points.

Remove the infrequent group from the overall numbers, and the aggressive dropshotters won a mere 53.4% of points in which they used the tactic.

53.4% isn’t awful–if you win 53.4% of the points in a match, you almost always win.  However, the type of point in which the drop shot makes sense isn’t an average point.  Usually the dropshotter has better court position than his opponent, who may be off-balance or far behind the baseline.  This isn’t always the case, especially when the dropshotter is simply trying to end the point, or when his brain stops working.  But in the majority of cases, the dropshotter has such an advantage in court position, it seems likely that a more common tactic–such as an aggressive groundstroke, perhaps followed by a net approach–would do better.

Another consideration goes beyond the outcome of a specific point.  A player who fails to run down a drop shot will probably remember that lost point for a game or two and play a little closer to the baseline, maybe making himself less comfortable in the process.  It’s possible that the long-term effect gives an advantage to the player who regularly uses the tactic.

But somewhere between Gonzalez’s four drop shots on Sunday and Volandri’s 23, the marginal advantage of each additional dropper must wear off.  I find it hard to imagine that one drop shot per game has any more of a long-term strategic effect than one drop shot per three games.  If that’s true, Volandri hit 13 or 14 more drop shots than required.  Thus, in about 8% of Sunday’s 162 points, he took an advantageous court position and wasted it on an even-odds shot.

More evidence will surely give us a fuller picture of drop-shot tactics on clay courts.  We may be able to determine whether there is a post-dropper “hangover effect” and if so, how many drop shots are required to reap the benefits.  Until then, it’s worth considering whether drop shots are worth the risk, especially when there may be such a high-percentage alternative.

The Speed of Every 2013 Surface

Few debates get tennis fans as riled up as the general slowing–or homogenization–of surface speeds.  While indoor tennis (to take a recent example) is a different animal than it was fifteen or twenty years ago, it’s tough to separate the effect of the court itself from the other changes in the game that have taken place in that time.

Further, the “court effect” itself is multi-dimensional.  The surface makes a big difference, as grass will almost always play quicker than a hard court, which will usually play faster than clay.  But as we’ve seen with the persistence of Sao Paulo as one of the fastest-playing events on tour, altitude is a major factor, as is weather, which can slow down a normally speedy tournament, as was the case with Hurricane Irene at the 2011 US Open.  The choice of balls can influence the speed of play as well.

With all of these factors in play, what we often refer to as “surface speed” is really “court speed” or even “playing environment.”  It’s not just the surface.  That said, I’ll continue to use the terms interchangeably.

Because of there is only limited data available, if we want to quantify surface differences,  we must use a proxy for court speed.  What has worked in the past is ace rate–adjusted for the server and returner in each match.  On a fast court–a surface that doesn’t grip the ball; or one like grass with a low, less predictable bounce; or at a high altitude; or in particularly hot weather–a player who normally hits 5% of his service points for aces might see that number increase to 8%.  (Returners influence ace rate as well. A field with Andy Murray will allow fewer aces than a field with Juan Martin del Potro, so I’ve controlled for that as well.)

Aggregate these server- and returner-adjusted ace rates, and at the very least, we have an approximation of which courts on tour are most ace-friendly.  Since most of the characteristics of an ace-friendly court overlap with what we consider to be a fast court, we can use that number as an marker for surface speed.

2013 Court Speed Numbers

For the second year in a row, the high-altitude clay of Sao Paulo was the fastest-playing surface on tour.  The altitude also appears to play a role in making Gstaad quicker than the typical clay.

As for the slowing of indoor courts, the evidence is inconclusive.  The O2 Arena, site of the World Tour Finals, rated as slower than average in 2011 and 2012, on a level with some of the slowest hard courts on tour.  This year, it came out above average, and a three-year weighted average puts the O2 at the exact middle of the ATP court-speed range.

Valencia and the Paris Masters played about as fast as they have in the past, while Marseille remained near the top of the rankings. If there is evidence for a mass slowing of indoor speeds, it comes from some unlikely sources: Both Moscow and San Jose were among the quickest surfaces on tour in 2010 and 2011, but have been right in the middle of the pack for the last two years.

The table below shows the relative ace rate of every tournament for the last four years, along with a weighted averaged of the last three years.  The weighted average is the most useful number here, especially for the smaller 28- and 32-player events.  The limited extent of a 31-match tournament can amplify the anomalous performance of one player–as you can see from some of the bigger year-to-year movements.  But over the course of three years, individual outliers have less impact.

The “Sf” column is each event’s surface: “C” for clay, “H” for hard, and “G” for grass.  The numbers are multipliers, so Sao Paulo’s three-year weighted average of 1.58 means that players at that event hit 58% more aces than they would have on a neutral court.  Monte Carlo’s 0.67 means 33% less than neutral.

Event            Sf  10 A%  11 A%  12 A%  13 A%   3yr  
Sao Paulo        C    1.44   1.08   1.58   1.74  1.58  
Marseille        H    1.09   1.24   1.41   1.26  1.30  
Halle            G    1.20   1.39   1.26   1.20  1.25  
Wimbledon        G    1.36   1.18   1.24   1.25  1.24  
Shanghai         H    0.96   1.05   1.08   1.37  1.22  
Montpellier      H    1.28          1.40   1.16  1.21  
Brisbane         H    1.01   1.20   1.08   1.27  1.19  
Tokyo            H    1.35   0.98   1.17   1.26  1.18  
Gstaad           C    0.87   1.13   0.90   1.35  1.16  
Winston-Salem    H           1.20   1.10   1.18  1.16  

Chennai          H    0.75   0.77   1.21   1.25  1.16  
Valencia         H    1.02   1.10   1.12   1.19  1.15  
Zagreb           H    1.09   1.16   1.20   1.11  1.15  
Washington       H    0.96   0.93   1.34   1.10  1.15  
Vienna           H    1.42   1.22   1.01   1.19  1.14  
Santiago         C    1.23   1.21   0.86   1.29  1.13  
Sydney           H    1.08   1.14   0.94   1.25  1.13  
Atlanta          H    0.92   0.82   1.06   1.26  1.12  
Eastbourne       G    1.07   1.13   0.92   1.22  1.11  
Queen's Club     G    1.07   1.13   1.09   1.12  1.11  

Paris            H    1.38   0.97   1.16   1.12  1.11  
Cincinnati       H    1.09   1.02   1.08   1.13  1.10  
s-Hertogenbosch  G    1.13   1.08   1.03   1.15  1.10  
Auckland         H    1.01   1.08   1.06   1.12  1.09  
Memphis          H    1.08   1.12   0.95   1.09  1.05  
Stuttgart        C    1.09   1.05   1.04   1.06  1.05  
Bogota           H                         1.09  1.05  
Rotterdam        H    0.88   1.21   0.83   1.12  1.04  
Stockholm        H    0.93   0.96   1.15   0.99  1.04  
Basel            H    0.98   1.05   1.16   0.96  1.04  

Bangkok          H    1.20   1.12   0.73   1.19  1.03  
Australian Open  H    0.98   1.10   0.92   1.08  1.03  
US Open          H    1.14   0.93   1.06   1.04  1.03  
San Jose         H    1.21   1.23   0.96   0.99  1.02  
Moscow           H    1.28   1.12   1.01   0.99  1.02  
Dubai            H    1.13   1.07   1.14   0.92  1.02  
Doha             H    0.88   1.29   0.90   0.98  1.00  
Tour Finals      H    1.07   0.93   0.87   1.11  1.00  
Beijing          H    1.01   1.01   1.06   0.94  0.99  
Canada           H    0.99   1.02   1.04   0.95  0.99  

Madrid           C    0.76   0.86   1.19   0.89  0.98  
Kitzbuhel        C           1.12   0.70   1.12  0.98  
Metz             H    1.14   0.96   1.07   0.90  0.97  
Dusseldorf       C                         0.92  0.96  
Munich           C    0.77   0.82   0.91   0.97  0.92  
St. Petersburg   H    1.02   0.84   0.86   0.99  0.92  
Acapulco         C    0.88   0.89   1.06   0.84  0.92  
Delray Beach     H    0.98   1.07   0.92   0.85  0.91  
Newport          G    1.46   0.72   1.04   0.89  0.91  
Kuala Lumpur     H    0.96   0.97   0.81   0.94  0.90  

Miami            H    0.91   0.98   0.86   0.89  0.89  
Umag             C    0.56   0.74   0.67   1.04  0.87  
Hamburg          C    1.04   0.85   0.75   0.92  0.85  
Buenos Aires     C    0.84   0.86   0.93   0.74  0.82  
Indian Wells     H    0.92   0.90   0.86   0.77  0.82  
Roland Garros    C    0.82   0.86   0.81   0.78  0.81  
Barcelona        C    0.73   0.65   0.91   0.78  0.80  
Casablanca       C    0.82   0.91   0.77   0.75  0.79  
Estoril          C    0.62   0.73   0.79   0.71  0.74  

Houston          C    0.85   0.71   0.71   0.77  0.74  
Bucharest        C    0.61   1.08   0.62   0.68  0.73  
Rome             C    0.78   0.67   0.64   0.81  0.73  
Nice             C    0.88   0.84   0.79   0.64  0.72  
Bastad           C    0.93   0.74   0.86   0.58  0.70  
Monte Carlo      C    0.63   0.60   0.71   0.67  0.67

Berdych, Djokovic, and Stars in Davis Cup

Tennis fans–especially the more old-fashioned among us–tend to agree on some things that players should always do.  Among them: revere Wimbledon, admit to a net touch, and play Davis Cup.

The top singles players on the two sides of last weekend’s tie between Serbia and the Czech Republic are good examples of what fans like to see.  Tomas Berdych has played 12 of 14 Davis Cup ties while a member of the top ten, and in that time, the Czech team has never lost a tie because he didn’t show up.  Novak Djokovic hasn’t been quite as reliable, playing singles in 13 of 18 ties since breaking into the top ten, though of the five he didn’t play, Serbia lost only one.

However, plenty of tennis megastars have been even more consistent cogs on their national teams.  In the years when Goran Ivanisevic was in the top ten, his Croatian team played ten ties, and Goran was there for all 10.  Since 1991, three other players have played at least ten ties while missing only one: Yevgeny Kafelnikov, Lleyton Hewitt, and Michael Stich.

Aside from Berdych and Djokovic, today’s top players are not so reliable.  Roger Federer has participated in 14 of 24 ties since he became a top-tenner, and the Swiss side has lost eight of the ten ties he’s missed.  Andy Murray has offered his services for only 5 of 12 as a top ten player, and the Brits have lost four of their seven Murray-less weekend.

Even less of a Davis Cup stalwart than Murray, however, is Rafael Nadal.  Thanks to a combination of injury, fatigue, and a frequent lack of necessity, Rafa has played singles in only 10 of 25 ties since breaking into the top ten.

The table below compares all players who, since 1991, have been in the top ten while their countries played at least ten Davis Cup ties.  It shows their record when participating (“In W-L”), their team’s success rate when they sat out (“Out W-L”), the percentage of ties in which they took part (“In%”), and the percentage of ties in which either they played or their team won anyway (“AllGood%”).

(I only count someone as participating if he contested at least one singles match.  In a few cases–such as Serbia’s defeat last year of Sweden, in which Djokovic only played doubles–that blurs the line between wins with and without the player.)

Player              In W-L  Out W-L     In%  AllGood%  
Goran Ivanisevic       5-5      0-0  100.0%    100.0%  
Yevgeny Kafelnikov    13-6      0-1   95.0%     95.0%  
Lleyton Hewitt        10-3      0-1   92.9%     92.9%  
Michael Stich          8-2      0-1   90.9%     90.9%  
Andy Roddick          15-5      0-3   87.0%     87.0%  
David Nalbandian      11-2      0-2   86.7%     86.7%  
Tomas Berdych          9-3      2-0   85.7%    100.0%  
Carlos Moya            8-4      1-1   85.7%     92.9%  
Stefan Edberg          8-3      2-0   84.6%    100.0%  
Marcelo Rios           5-3      2-0   80.0%    100.0%  
Novak Djokovic        10-3      4-1   72.2%     94.4%  
Nikolay Davydenko      8-3      4-1   68.8%     93.8%  
David Ferrer           7-2      3-2   64.3%     85.7%  
Marat Safin            7-0      2-3   58.3%     75.0%  
Roger Federer         10-4      2-8   58.3%     66.7%  
Boris Becker           5-2      5-3   46.7%     80.0%  
Andy Murray            3-2      3-4   41.7%     66.7%  
Jim Courier            6-0      6-3   40.0%     80.0%  
Rafael Nadal           9-1     10-5   40.0%     80.0%  
J M Del Potro          1-3      6-1   36.4%     90.9%  
Pete Sampras           8-3     16-6   33.3%     81.8%  
Andre Agassi           7-2    14-10   27.3%     69.7%  
Michael Chang          2-1     13-3   15.8%     84.2%

Doubles Wins and Davis Cup Results

Today, Tomas Berdych added another chapter to his outstanding Davis Cup doubles career, partnering Radek Stepanek to give his Czech Republic a 2-1 lead in this weekend’s Davis Cup final.

The absence of Janko Tipsarevic meant that the doubles rubber was particularly crucial.  While Novak Djokovic will probably defeat Berdych tomorrow, Stepanek is equally likely to dismiss Dusan Lajovic, giving the Czechs a second consecutive Davis Cup title.

Since the Saturday doubles match is so often a pivotal juncture in a Davis Cup tie, I was curious whether the doubles match was particularly predictive of the end result.  If you’re a believer in momentum, it would seem possible.

However, if a side is to take a 2-1 lead, it’s better to win two singles matches and lose the doubles than to drop one of the singles matches.  Or, to put it another, probably more accurate, way: It’s best to have a squad that dominates the singles.  (Stunning insight, I know.)

There have been 435 World Group ties (including playoffs) since 1981 in which the outcome was undecided after the doubles match.  In 296 of those, the two sides split the singles.  In the other 139, one side swept the first-day singles and the opposing team won the doubles.

Of the first group of 296, the side that won the doubles won 80.4% of ties.  That pales in comparison to the singles-sweeping sample. Of those 139 ties, the side that won both singles and lost the doubles proved triumphant 93.5% of the time.

This shouldn’t be too surprising.  Momentum or no momentum, the third day of a Davis Cup tie is nothing but singles matches.  When the outcome is to be decided by two singles rubbers, would you rather have two great singles players or a pair of momentum-swaying doubles players?

Fortunately for the Czechs, 80% is still awfully good, and it probably understates the likelihood that Stepanek will beat Lajovic tomorrow.   Nice as it would have been to sweep opening-day singles, it helps to have a backup plan when Djokovic is playing for the other side.

In Search of Davis Cup Heroes

Come up big for one important weekend, and you can earn a reputation as a Davis Cup hero that lasts a lifetime.  We tend to remember big stories and crucial moments more than career-long trends, so images of Radek Stepanek holding last year’s trophy loom larger in memory than his mediocre-sounding 12-11 record in live singles rubbers.

This isn’t to say that Stepanek isn’t a Davis Cup hero.  Some matches are more important than others, and even 12-11 can be impressive when you consider that four of his 11 losses came against top-ten players.  And that’s to say nothing about doubles.

To find out who really performs under the scrutiny of Davis Cup crowds, we need to go deeper.  We must determine how many matches a player like Stepanek should’ve won, then compare his actual mark.  When we do that with two decades of Davis Cup results, we find some unsung stalwarts and some overrated superstars.  The international competition isn’t the endless source of upsets that pundits like to insist it is, but some players do provide us with more upsets than others.

Here’s how it works.  For every live Davis Cup rubber, we take each player’s ranking and estimate the likelihood that each player would win the match.  In the case of today’s match between Stepanek and Novak Djokovic, we might estimate that the Serbian has a 95% chance of winning.  Then we compare the results.  If Novak wins, he’ll outperform expectations by five percentage points (100% instead of 95%), while the Czech underperforms by the same amount (0% instead of 5%).

Do that for every match, tally the results for every player, and things start to get interesting.

Among active and recently-active players, there’s an unusual twosome near the top of the rankings: Juan Martin del Potro and David Nalbandian. (Delpo partisans will be glad to know that he just edges out his older compatriot.)  Del Potro has won 11 of 15 live rubbers, though based on his competition, we would only have expected him to win eight.  Four of those wins were over higher-ranked players.  Nalbandian is a stunning 23-6 in live singles rubbers (including 6-4 against higher-ranked players), while we would have expected him to win between 17 and 18.

Both Argentines have outperformed their rankings, winning between 32% (Nalbandian) and 36% (Delpo) more matches than we would expect.  Of those with at least ten live rubbers under their belts, the only active player to better those marks is Frank Dancevic.  The Canadian has won three live rubbers despite never facing a lower-ranked player in any of his ten matches.  3-7 may not seem awe-inspiring, but the numbers suggest he should have won only one match, with an outside shot at a second.  He has more than doubled that.

(I’m setting the standard here at 10 live rubbers. But it would be foolish to ignore Amir Weintraub, who has been historically great in his seven live rubbers.  Like Dancevic, he has never faced a lower-ranked player in Davis Cup, yet he has amassed a 4-3 record, despite an expectation of between one and two wins.)

How about the familiar faces this weekend?  Stepanek has racked up about 13% more Davis Cup singles wins than expected, while Tomas Berdych is slightly positive, at +4%.  Djokovic and his almost-teammate Janko Tipsarevic are a bit below expectations.  This isn’t really a knock on Novak, though.  When you’ve spent so many years close to top, expectations are very high.  Also, his two high-profile Davis Cup retirements–against Delpo in 2011 and against Nikolay Davydenko in 2008–count against him.  Take out those two matches, and his mark swings to a +4%, equal to Berdych.

In any event, no modest over- or underperformance is likely to swing the singles matches in this weekend’s tie.  Even a sluggish Djokovic would probably whip a hero-mode Stepanek.  Neither Novak or Berdych has displayed enough of a Davis Cup-specific tendency to alter the outcome of their match.  And Tipsarevic’s replacement, Dusan Lajovic, would need to channel his inner Dancevic to have any impact at all.

If hero-mode Stepanek is to alter the course of this tie, it will probably happen in the doubles rubber.  Unfortunately for Radek, I don’t have the numbers to disprove a strong suspicion that the most outrageous overperformance in Davis Cup this year belongs to Ilija Bozoljac, one of the men who will be standing across the net from him for–we can only hope–five sets tomorrow.

After the jump, I’ve included +/- numbers like those cited above for many top-ten and otherwise interesting players.

Continue reading In Search of Davis Cup Heroes

Challenger Tour Finals Forecast

I wrote an extensive preview of this week’s Challenger Tour Finals for The Changeover, so you should check that out first.  (Also worth a read is the preview at Foot Soldiers of Tennis.)

Because so much less separates players at this level (compared to those at last year’s World Tour Finals), my forecast stops just short of throwing its hands up in dismay.  Coming into the event, Italian clay specialist Filippo Volandri was the favorite, with a 15.5% chance of winning the event.  He lost today to Alejandro Gonzalez, making it much less likely that he’ll progress out of the round-robin stage.

Today’s other winners were top seed Teymuraz Gabashvili, Oleksandr Nedovyesov, and Jesse Huta Galung.  My numbers now consider Huta Galung the favorite, with a better than 20% chance of winning the title.  The situation in Grupo Verde will become much more clear after tomorrow’s night match between Gabashvili and Nedovyesov.

Here is the pre-tournament forecast:

Player       3-0  2-1  1-2  0-3     SF      F      W  
Gabashvili   12%  38%  37%  13%  49.8%  24.3%  12.0%  
Volandri     15%  40%  35%  10%  55.3%  29.3%  15.5%  
Nedovyesov   14%  39%  36%  11%  53.0%  26.9%  13.7%  
Huta Galung  14%  39%  36%  11%  53.8%  28.2%  14.6%  
Gonzalez     10%  35%  40%  15%  45.0%  21.8%  10.4%  
Ungur        10%  35%  40%  15%  45.0%  20.9%   9.8%  
Martin       11%  36%  39%  14%  46.0%  22.4%  10.7%  
Clezar       13%  38%  37%  11%  52.2%  26.3%  13.3%

And here is the forecast updated with the results of today’s four matches:

Player       3-0  2-1  1-2  0-3     SF      F      W  
Gabashvili   24%  50%  26%   0%  71.5%  35.0%  17.1%  
Volandri      0%  27%  50%  23%  30.2%  16.2%   8.6%  
Nedovyesov   28%  50%  22%   0%  75.7%  38.3%  19.5%  
Huta Galung  27%  50%  23%   0%  74.7%  39.0%  20.5%  
Gonzalez     23%  50%  27%   0%  70.1%  33.7%  15.8%  
Ungur         0%  22%  50%  29%  23.1%  10.8%   5.1%  
Martin        0%  23%  50%  27%  25.1%  12.2%   5.9%  
Clezar        0%  27%  50%  23%  29.6%  14.9%   7.4%

(My algorithm doesn’t implement the details of the number-of-sets-won tiebreaker, so Guilherme Clezar, the only loser today to win a set, probably has a slightly better chance of advancing than these numbers give him credit for.)

—

Challenger charting: The most interesting match of the day–if not the cleanest–was the last one, between Nedovyesov and Clezar.  I charted it, so you can check out detailed serve, return, and shot-by-shot stats for that contest.

And if you’re really into this stuff–Challengers and/or charting–here are my stat reports from yesterday’s first-round matches in Champaign between Ram and Giron and Sandgren and Peliwo.

Rafael Nadal, Top Twosomes, and the Future

The only match that either Rafael Nadal or Novak Djokovic lost in London was the final, when Nadal fell to Djokovic.  It was a good summary of the season as a whole.  The top two weren’t undefeated for the entire season, but they might as well have been.

Between them, Rafa and Novak lost only 16 matches this year, six of them to each other.  Fittingly, they split those six matches.  No single player poses a serious threat to their dominance.  Only Juan Martin del Potro defeated both this year, and he lost his five other encounters with the top-ranked duo.  The injured Andy Murray remains only a wildcard, having split Grand Slam finals with Djokovic this year but without having played Nadal since 2011.

Barring a huge upset loss in Davis Cup, Djokovic will end the season with the best-ever winning percentage for a #2-ranked player.  His 88.9% just edges out the 88.7% posted by Nadal in 2005, when he finished second to Roger Federer.  In the last thirty years, only five other #2’s won at least 85% of their matches.

Taking these six prior pairs as the best single-year twosomes the ATP has recently produced, it’s surprising to see what happened to them the following year.  In three of those seasons, neither of the ultra-dominant duos finished the next season at #1.  A third player overcame them both.

Here is the list of the seven most dominant twosomes of the last thirty years, along with their year-end rankings 12 months after the end of their notable seasons (Nx):

Yr  #1              W-L    Nx  #2              W-L    Nx  
83  John McEnroe    62-9    1  Mats Wilander   74-11   4  
85  Ivan Lendl      83-7    1  John McEnroe    72-10  14  
87  Ivan Lendl      70-7    2  Stefan Edberg   76-12   5  
89  Ivan Lendl      80-7    3  Boris Becker    58-8    2  
05  Roger Federer   81-4    1  Rafael Nadal    79-10   2  
12  Novak Djokovic  75-12   2  Roger Federer   74-13   6  
13  Rafael Nadal    76-7    ?  Novak Djokovic  72-9    ?

In 1988, Mats Wilander overcame both Ivan Lendl and Stefan Edberg to claim the #1 position.  In 1990, it was Edberg who leapfrogged Lendl and Boris Becker.  This year, of course, Nadal reclaimed the top spot from last year’s top two of Djokovic and Federer.

Those of us who watched the Tour Finals for the last week might find it hard to imagine that anyone–certainly not any of the other six men in London–would outperform either Rafa or Novak over the course of a season.  But injuries strike, slumps take hold, and–unlikely as it may seem in 2013–young players emerge and dominate. For all of the radical changes in the game since the late 80s, these precedents serve as an important reminder of the unpredictability of tennis.

Novak Djokovic and Neutralizing the Second Serve

Italian translation at settesei.it

When Novak Djokovic stands on the other side of the court, you’d better make some first serves.

Djokovic is one of only two players this year to win more than 55% of second-serve-return points (David Ferrer is the other).  When you consider that he also wins more than 35% of first-serve-return points, it’s less clear that the server has much of an advantage.  In fact, when Novak is performing at that level, if his opponent goes through a bad patch and only makes a quarter of his first serves, Djokovic has a better than 50% chance of breaking serve.

Commentators often refer to Djokovic’s return as a weapon, and they’re not joking.  Only six players (including Novak himself and, invariably, John Isner) won as many second-serve points as Novak won second-serve-return points.

What’s most remarkable about his return game is how quickly he neutralizes the second serve, often using tactics that, in the hands of lesser mortals, would be more appropriate for service points.  Unlike other returners, he is somewhat more likely to win a short return point than a long one.  While other players need a few shots to negate the advantage conferred by serving, Djokovic is most effective early in service points.

This graph shows the percentage of second-serve-return points won by Djokovic, by rally length, in four matches I’ve charted (US Open vs Stanislas Wawrinka and Rafael Nadal; Tour Finals vs Wawrinka and Juan Martin del Potro), compared to the the same percentage for other top-ten players (excluding Rafael Nadal) in 19 other matches I’ve charted from the US Open and Tour Finals this year:

novak1

When the return lands in play, Djokovic wins almost 53% of return points, while the pack manages less than 44%.  (All of these matches are between top-ten opponents, so the averages are much lower than season numbers, which are affected by matches against lesser opponents.)  The difference stays about the same when we take out 2- and 3-shot rallies.

When we limit our view to points that reach six shots, Novak still has a substantial edge, roughly 48% to 42%.  But in points longer than seven shots, there’s virtually no difference.

Djokovic’s return is so good that if his opponent misses his first serve, the point has turned into a Novak service point.  Opponents are forced to fight their way into their own service points!

This was particularly true in the Djokovic-Nadal US Open final.  (Follow the link, then click the ‘Serve Influence’ tab for a shot-by-shot winning percentage breakdown.)  Nadal won barely half of his second-serve points when Djokovic got his return in play, but once the rally reached five shots (or six, or seven, and so on), Nadal had the edge, winning 60% of points.  From the five-shot mark, Rafa’s advantage only increased.

Of course, Nadal won that match.  It’s not quite so useful to convert return points into service against an opponent whose own return of serve is so effective.  To win today, Novak needs to do more than just attack Rafa’s second serve.  He must either do so even more effectively than he did in New York, or put himself in a better position to win longer return points after the effect of his return has worn off.

Round Robin Shutouts

At this year’s World Tour Finals, we were spared the knottiest sort of round robin tiebreakers.  Each group had a clear winner (Rafael Nadal and Novak Djokovic) who went undefeated, along with another player (David Ferrer and Richard Gasquet) who failed to win a single match.

Since 1987, 33 players have recorded a 3-0 record in Tour Finals round-robin play.  This year is the first time since 2010 (Nadal and Roger Federer) that two players have done so, and before that, we have to go back to 2005 (Federer and Nikolay Davydenko).  It’s not that rare of an event–this year is the 11th time since 1987 that two players have beaten every opponent in their group.

Undefeated players are hardly guaranteed further advances, however.  Those 33 undefeated competitors have a mere 17-16 record in the semifinals, and the 17 men who reached the final won the title only nine times, against nine final-round losses.  (Twice, two undefeated players faced off in the finals–the aforementioned 2010 event along with 1993, when Michael Stich and Pete Sampras contested the title.)

The tiny sample of three round-robin matches pales in predictive value next to the old standby of ATP ranking.  In the last 26 years, the higher-ranked player has won 16 finals.  In the more top-heavy 21st century, the title has gone to the man with the superior ranking 11 of 13 times.  (Advantage: Nadal.)

That said, the gap between the two finalists is traditionally greater than it is expected to be tomorrow.  (If Stanislas Wawrinka upsets Novak Djokovic in the second semifinal, you can disregard this paragraph.  Sorry, Stan, but I’m betting against you.)  Only twice in the round-robin era have the top two players in the ATP rankings met in the concluding match of the Tour Finals–2010 (again) and 2012 (Djokovic d. Federer).

Not a shutout, but shut out

Exactly as many players–33 through 2012–have gone 0-3 in the round robin as the number who did the opposite.  Ferrer and Gasquet find themselves in quality company.

Ferrer is the 7th player ranked in the top three to lose three round robin matches.  In 2001, #1 Gustavo Kuerten was winless, only a year after claiming the championship.  Jim Courier (1993), Juan Carlos Ferrero (2003), and Nadal (2009) went 0-3 from a #2 ranking, while Thomas Muster (1995) and Djokovic (2007) did so while ranked #3.

Ferrer is notable for another dubious achievement: going 0-3 twice.  He previously did so in 2010, so this year, he matches the mark of Michael Chang, the only other man in the round-robin era to post multiple 0-3s, having gone winless in both 1989 and 1992.

His age may work against him, but there is a glimmer of hope for Ferrer.  Four players (including Kuerten, mentioned above) have gone 0-3 at one Tour Finals and won the title at another.  Andre Agassi was winless in 1989, then won the event in 1990.  Stich was 0-3 in 1991, then claimed the title in 1993.  As we’ve seen, Djokovic failed to win a single match in 2007, yet came back to win the tournament in 2008.  (Then did so again last year.)

If Nadal wins tomorrow, we can add one more name to this list, in his case finally adding the trophy to his collection four years after suffering through a winless week.  His 4-0 record so far this week may be no guarantee of success in the final, but it will hardly count against him.

—

Match reports: I charted today’s Federer-Nadal semifinal, as well as yesterday’s Federer-del Potro match.  Click the links for exhaustive serve, return, and shot statistics.

Worth a read: Carl Bialik analyzes ATP rematches–pairings like Fed-Delpo that faced off in back-to-back weeks.  As usual, we have to rewrite the rules for Rafa.