Has Too Much Play Finally Caught Up with Top Men?

The 2017 US Open draw is out. But much of the talk this year will be on the names not included in the draw.

As exciting as the final slam of the year could prove to be, it will be hard not to feel the absence of some of the sport’s biggest names. Serena Williams and Victoria Azarenka will be missing from the women’s draw this year. Williams because of the approaching due date of her first child and Azarenka owing to a fraught custody battle over her newborn son.

The top of the draw will be even more depleted on the men’s side. But unlike the absent top female players, who are missing the US Open because of family issues, the absent among the men are by and large missing due to injury.

Short Seasons on the ATP

During the final stretch of the 2017 season, every other week seems to bring a new announcement of a top male player who is shutting his season down. The string of announcements began with Novak Djokovic, who ended his season in late July owing to an injured elbow. Nearly a week later, Stan Wawrinka cut his 2017 short to address a knee injury. In the next week, Kei Nishikori became the third top 10 male to bring his season to a close, in his case to rehabilitate a right wrist.

We only have to look at the US Open’s men draw to see the consequences of these trends. Just 7 of the top 10 ranked men will be competing in Flushing Meadows. The only other US Open draw in the Open Era that ties that low is 1996. Yet only two of the three, Jim Courier and Boris Becker, were out due to injury. The third, Yevgeny Kafelnikov, skipped the event out of spite.

Game Age

It is possible that the spike in injuries in recent weeks is just a fluke. However, this isn’t the first sign we’ve seen of a worn-out tour in 2017. One of the biggest talking points to come out of this year’s Wimbledon Championships was the high number of retirements in the first week. By the third round, there were 14 retirements among the men and women, the highest on record at an Open Era Grand Slam.

If it is the case that we are seeing a general fatigue at the top of the tour this year, what could be the cause?

Some might argue that “old age” has finally caught up with the tour’s top players. The success of 30+ players has been a well-accepted phenomenon for a number of years. But to attribute post-30 play to the injury issues that have cropped up this year wouldn’t be consistent with the reality that the majority of players who have cut their seasons short haven’t passed year 30 yet.

Another, and I think more interesting, possibility is the intensity of play. Play intensity could encompass many things: minutes played, shots hit, or energy expended on court. Unfortunately, if we want to be able to look at how intensity in play has varied over many tennis generations, we don’t have many options for quantifying play intensity in a similar way over many years.

The most comprehensive intensity stat we have for all matches in the Open Era is games played. Obviously games played doesn’t capture a lot of what we would like about intensity of play, like the duration or shots played during points, but it has the advantage of comprehensiveness across years.

Using the games played we can define the “game age” of top players as the total games played up to a certain age. For this post, I am going to focus only on players who were ever ranked in the top 100 and I will count all professional matches at all tour levels, Davis Cup, Olympics, etc. Players are grouped by their generation, in five year groups, according to the first year they played a professional match.

Since the mid 1970s, the trends shown in the chart above indicate a clear increase in game age of top male players across the age span. Before 1990, players were typically 30 years or older before they tallied 10K professional games played (median game age is shown by the solid lines, 25th and 75th percentiles are shaded). For the 1990 to 1994 generation, the 10K age was 28, for 1995 to 2004 is was 27, and for 2005-2009 the 10K age decreased to 26.

By 35 years of age, players of the 1975 to 1979 generation would have accumulated a median of 11K games. Players of the 80s rose the game age at 35 to 15K. For the 1990 to 1994 cohort, they could expect to have played 19K games by 35. For top players starting their career in the new millennium, game age at 35 is expected to be well over 20K.

The stark rise in game play among today’s tennis players raises a bit of a paradox for the sport. How can players be playing so much yet playing for longer?

Whether it is overall better fitness, wiser calendar selection, improved recovery strategies, or something else, there are clearly counterbalancing factors at work that have allowed the sport to take on such an increase in play intensity in recent decades.

Yet even those career-lengthening factors must also have their limits. And 2017 has given us the first troubling signs that the trends in game play have taken a turn for the worse.

The code and data for this post can be found here.