In the last few weeks, we’ve seen some overall serving trends–how righties and lefties perform in the deuce and ad courts, and how successful they are at specific point scores.
The tour-wide results are interesting enough, but there’s much more to discover at the individual player level. Because point-by-point data is only available for 2011 grand slam matches, only a few players have had enough points tracked to allow us to make meaningful conclusions. Fortunately, those are the best players in the game, and there’s plenty to discover.
Let’s start with Novak Djokovic. Much of his success seems to stem from rock-solid consistency: he can attack when returning almost as much as most players do on serve; he is strong on both forehand and backhand, and he rarely shows signs of mental weakness. If there is a player who doesn’t display the typical differences between deuce and ad courts and various point scores, it would seem to be Djokovic.
The first table shows the frequency of different outcomes in the deuce court, in the ad court, and on break point, relative to Djokovic’s average. For instance, the 1.018 in the upper left corner means that Djokovic wins 1.8% more points than average in the deuce court.
OUTCOME Deuce Ad Break
Point% 1.018 0.980 0.975
Aces 1.117 0.869 1.046
Svc Wnr 1.101 0.886 0.865
Dbl Faults 1.176 0.802 1.102
1st Sv In 1.028 0.968 1.081
Server Wnr 1.027 0.970 0.815
Server UE 0.973 1.030 0.941
Return Wnr 0.972 1.031 2.125
Returner Wnr 0.832 1.189 1.487
Returner UE 0.927 1.082 1.092
Rally Len 0.938 1.070 1.184
There are some huge differences here. Given the gap between deuce and ad results for many types of outcomes, it’s surprising that Novak wins so many ad-court points. He hits nearly 12% more aces in the deuce court, suggesting that even when he doesn’t hit an ace or service winner, he better sets up the point. Returners are much more likely to hit winners against him in the ad court, and the point requires more shots.
There are even more extreme numbers on break point. It’s unclear from the numbers whether Djokovic consistently goes for more on the serve on break point–more aces, fewer service winners, more double faults, but more first serves in–but it appears he plays much more gingerly, hitting far fewer winners and allowing opponents to hit more than twice as many return winners than average.
Next, this is how he performs on a point-by-point basis. Win% shows what percentage of points he wins at that score; Exp is how many he would be expected to win (given how he performs in each match), and Rate is the difference between the two. A rate above 1 means he plays better on those points; below 1 is worse.
SCORE Pts Win% Exp Rate
g0-0 360 70.0% 70.2% 1.00
g0-15 107 65.4% 68.5% 0.96
g0-30 37 59.5% 66.5% 0.89
g0-40 15 66.7% 64.8% 1.03
g15-0 248 66.5% 71.0% 0.94
g15-15 153 69.9% 69.9% 1.00
g15-30 68 67.6% 68.1% 0.99
g15-40 32 68.8% 66.7% 1.03
g30-0 165 67.3% 71.3% 0.94
g30-15 161 70.2% 70.4% 1.00
g30-30 94 77.7% 67.9% 1.14
g30-40 43 62.8% 66.4% 0.95
g40-0 111 73.9% 72.0% 1.03
g40-15 142 76.8% 71.3% 1.08
g40-30 106 67.0% 68.6% 0.98
g40-40 104 72.1% 66.8% 1.08
g40-AD 29 69.0% 66.2% 1.04
gAD-40 75 70.7% 67.0% 1.05
It appears that Djokovic’s caution on break point isn’t hurting him; despite losing a point or two more than expected at 30-40, he gets it back at 40-AD. Novak excels most in the pressure points: 30-30 and 40-40, with strong showings at nearly every point from 30-30 on, with the exception of 30-40–which may just be a fluke–we only have 43 points to work with.
We can go through the same exercises for Djokovic’s return points. The next two tables are trickier to read. Look at them as Serving against Djokovic. Thus, the number in the upper-left corner means that when serving against Djokovic, players win 1% more points than average in the deuce court.
(I’ve excluded return points against lefty servers, including Nadal. Since lefties and righties have such different serving tendencies, limiting the sample to righty servers gives us clearer results, even as the sample shrinks a bit.)
OUTCOME Deuce Ad Break
Point% 1.010 0.989 1.023
Aces 1.024 0.974 1.091
Svc Wnr 0.998 1.002 1.105
Dbl Faults 0.994 1.007 0.986
1st Sv In 1.055 0.940 0.957
Server Wnr 1.002 0.998 1.091
Server UE 0.987 1.015 0.964
Return Wnr 1.123 0.867 0.849
Returner Wnr 0.895 1.114 1.124
Returner UE 0.858 1.153 1.069
Rally Len 0.992 1.009 0.959
It seems that Novak goes big on the return in the deuce court, but tries to do more later in ad-court points. The break point tendencies may speak to other players’ fear of Djokovic’s return game: They go bigger with their serve, hitting more aces and service winners, and severely limiting Novak’s return winners. In the end, though, it doesn’t matter: he converts the break points anyway.
Here’s more on Djokovic’s return game, again with numbers from the perspective of players serving against him.
SCORE Pts Win% Exp Rate
g0-0 346 58.7% 56.3% 1.04
g0-15 143 53.1% 55.1% 0.96
g0-30 67 52.2% 53.9% 0.97
g0-40 32 53.1% 53.0% 1.00
g15-0 198 62.1% 57.2% 1.09
g15-15 151 54.3% 56.0% 0.97
g15-30 104 45.2% 54.7% 0.83
g15-40 74 59.5% 53.4% 1.11
g30-0 123 60.2% 58.1% 1.04
g30-15 131 51.9% 56.9% 0.91
g30-30 110 60.0% 56.0% 1.07
g30-40 88 54.5% 54.3% 1.00
g40-0 74 64.9% 59.0% 1.10
g40-15 94 61.7% 57.5% 1.07
g40-30 102 53.9% 57.2% 0.94
g40-40 189 50.8% 55.4% 0.92
g40-AD 93 54.8% 54.3% 1.01
gAD-40 96 55.2% 56.4% 0.98
While Djokovic excels at deuce (servers should win 55.4% of those points; they manage to win only 50.8%), the reverse happens at 30-30. There aren’t many clear trends here, which may simply attest to Djokovic’s return dominance, regardless of point score.