Players and fans tend to look at tiebreaks as a unique part of the sport of tennis, perhaps one susceptible to special skills. The ATP website last week devoted an article to what those skills might be. Players generally seemed to agree that it was nice to have a good serve, and a good return would also be handy. Clearly, more analysis is needed.
Let me give you my hypothesis. Tiebreaks are pressure packed, and pressure can affect any part of a player’s game. But in general, they should impact some parts more than others. You could make the case for either side of the ball–on the one hand, serving is a more “automatic” activity; on the other, there’s more time to think before each serve, and thinking can be dangerous when the pressure is on. This is where it’s nice to have some data.
I found 388 tiebreaks from the last eight ATP slams. For each one, I compared each player’s winning percentage on serve during the first 12 games of the set to his winning percentage on serve during the tiebreak. If players were robots, there might be a difference between the set and the tiebreak for any given match, but in general, the numbers should be the same.
But players aren’t robots. As it turns out, players win more return points than expected during tiebreaks. The difference is noticeable if not enormous: about one more return point than expected every three matches.
Thus, tiebreaks are different from the sets that precede them in one of two ways. Either some players are unable to serve up to their usual standard during tiebreaks, or some players manage to raise their return game in tiebreaks.
A breakdown by tournament suggests the answer. The difference between server winning percentage in sets and tiebreaks is about the same for the Australian Open, the US Open, and Wimbledon, but is less than half as much at the French. It seems, then, that faster courts give returners a bigger boost in the breaker. A more likely interpretation is that servers are unable to hold on to their advantage on faster courts. There’s less of an advantage to lose on clay.
My hypothesis at the outset focused on pressure, and combined with the numbers, it suggests that players are more affected by pressure when serving than when returning. It’s also possible that players find it more difficult to get into a serving rhythm with only two serve points at a time. It’s also possible that returners are less likely to concede aces during tiebreaks, meaning that the same serve quality and return potential results in more return points won.
Whether it is a matter of server timidity or returner aggression, there are certainly fewer aces in tiebreaks. In these 388 tiebreaks, there were 83 fewer aces than would be expected if players kept acing at the rate of their first twelve games. Given the relative infrequency of aces, that’s a more striking decrease than that of service winning percentage in general.
This analysis is hardly the final word. But for aspiring tiebreak masters, it does offer a slightly more specific prescription than “get better at tennis.” Rather than assuming that the tiebreak is all about the serve, recognize that returners have a slight advantage. On serve, players can improve simply by ignoring the pressure (easy, right?) and serving as well as they did during the set. When returning, players can be more aggressive in the knowledge that in general, servers will not be.
After all, a good serve may be the key to tiebreak success, but only if the serve is as good as usual in the breaker.