Written By: John McCool (Desertrose28)
Tennis is a young man’s game requiring a combination of endurance and short bursts of energy sustained over several hours. Point after point, tennis players face the daunting task of moving from the baseline to the front of the net in between returning 100 miles plus serves and hitting perfectly placed shots.
Other sports like baseball and golf require less wear and tear on the body. A first baseman that can hit a fastball and slow curve, and a golfer that consistently drives the ball 300 yards straight onto the fairway likely have a better chance of playing late into their 30s than most tennis players at this stage.
Tennis players tend to peak around 24 or 25 years old. For example, tennis legend Boris Becker won his last grand slam victory at 28. Similarly, John McEnroe and Bjorn Borg claimed their last grand slam titles at the ripe age of 25, which makes Roger Federer’s recent Australian Open victory all the more spectacular at age 35.
It makes sense that younger players tend to outlast older opponents over longer matches. To test this hypothesis, we analyzed 12,032 matches from 2012 through 2016. Matches that lasted less than 30 minutes were discarded from the analysis because the majority of these matches ended with a player injury.
Figure 1: The average difference between the winning and losing age (y-axis) against the match length (x-axis) between 2012 and 2016.
In our sample, matches that lasted less than the 77 minutes (below the first quartile) on average slightly favored older players. In these shorter matches, the average age difference between the winning and losing side was 0.37 indicating that older players tended to outlast their younger competition in short matches. The average age difference (between the winner and loser of the match) peaks around the 100-minute mark in the match and begins steadily swinging towards the young player’s favor all the way through the 215-minute point.
For reference, in 1,313 matches between the 150 and 215-minute mark, the average winning age was 27.4 compared the average losing age 27.5. During this 75 minute stretch, younger tennis players on average outlasted their older competition in every season but 2012.
Beyond the 215-minute mark, older players won more often than their younger counterparts. However, only 255 matches extended past this point. A larger sample size would give us a better idea of how younger players fair deep into matches (past 215 minutes).
Figure 2: Histograms of the average winning age (orange) and average losing age (blue) from 2012 through 2016.
The clash of the baby faces and grizzled veterans
While players in their late 20s and early 30s are less likely to win grand slam tournaments, the average winning age (27.7) eclipsed the average losing age (27.5) meaning that older players overall outplayed their younger counterparts between 2012 through 2016. In part, the average winning age is slightly skewed to the right because Roger Federer, Stan Wawrinka, and Rafael Nadal, each 30 years or older, are among the elite players in the ATP. On a whole, however, the average winning age for players in the ATP top 50 is 27.3 compared to 27.5 outside of the top 50.
If we remove players under 25 from the sample, the average winning age falls below the average losing age by -0.1 points marking a slight advantage to younger players. This result makes sense given that players in their late teens and early 20s are on average less experienced and have not likely reached their peak.
We also found that tennis veterans, 30 years or older, on average have the upper hand against players under 25. In head to head matches, the latter group won at a 53% clip over 1,621 matches.
In time, some of these younger tennis players will have a chance to win the next US Open or Wimbledon. Tennis is built for young legs and rewards those that can maintain a high playing level late into the match. As Nadal and Federer head towards retirement, a new crop of young prodigies including Alexander Zverev (19) and Thanasi Kokkinakis (20) are waiting in the wings and are ready to topple tennis’ aging elite.
 The four grand slam tournaments are the Australian Open, French Open, Wimbledon, and the US Open.