TennisOne Lessons

Predictability in Tennis

Daryl Fisher

If you watched the match between Roger Federer and Andy Roddick on television at this year’s US Open, then you had the pleasure to hear Andre Agassi as a guest commentator, and one of the most interesting facets of the exchange between Agassi and John McEnroe was with regard to how Federer seems to know where Roddick will serve

Andre Agassi revealed that he knew where Boris Becker was about to serve based on how Becker would place his tongue during his windup.

On this topic, Agassi revealed that he knew where Boris Becker was about to serve based on how Becker would place his tongue during his windup. This is amazing on at least two levels, the first being that Agassi would have noticed a correlation between Becker’s tongue and the placement of his serve, and the second being the value of unpredictability on the serve, especially at the higher levels of the game.

While many tennis players have not heard of what game theorists call the “strategy of unpredictability,” most tennis professionals regularly encourage this strategy by suggesting that players “mix up” their serves. This is excellent advice, and it implies that a player will win points on his serve more easily if he can prevent his opponent from anticipating where he will serve next. Unfortunately, many players forget this advice, especially in the heat of a competitive match. This article will explain how tennis players can become consistently unpredictable on their serves (assuming that you don’t have a “tell” like Becker).

The Importance of Unpredictability

Unpredictability becomes an important tennis strategy whenever predictability can be exploited. That is, if a player places his serves in a predictable way, his smart opponents can exploit this by preparing early and positioning themselves to play their strongest returns. Given that a player tries to make things harder for his opponents, preventing them from anticipating what he is about to do becomes important.

Pete Sampras had the best serve in the game partly because the placement was so difficult to read.

Though unpredictability is an important tennis strategy for most levels of tennis, it becomes increasingly important at the higher skill levels of the game where the difference between winning and losing is often very small. For example, one nationally ranked player who understands the advantage of anticipating his opponents’ serve placements said, “When I figure out my opponent’s serving pattern, he loses the first-strike advantage, and I gain it.” In fact, this player believes that nearly every opponent he plays has serving patterns that he can take advantage of, especially on critical points.

Players are More Predictable Than They Think

Most players probably already understand that their chances of winning a point are better if their opponents have trouble anticipating the placement of their serves, and so they try to mix up their serves. This is a reasonable plan, but most players are even predictable when they try to mix things up. If a player has some sort of system for mixing up her serves, she may think her opponent is not aware of it, but players must be careful. Especially at the higher levels, where smart opponents look for the subtlest clues as to where an opponent will serve next, any systematic thinking that a player applies can be discovered and exploited.

WTA player, Lindsey Lee-Waters practices this Four Corner Service Drill (click her to see the complete drill).

The problem with trying to be unpredictable with serve selections, as cognitive psychology and computer science research indicate, is that people are terrible at being random. That is, the human mind is not good at creating a “random” sequence, and, as a result, serve placement choices are more easily anticipated than players imagine. For an example of how difficult it is for people to be unpredictable, we can look to information science. In the book “Silicon Dreams,” Robert Lucky writes that a scientist at Bell Labs named David Hagelbarger built a surprisingly simple “mind-reading” machine. The machine was meant to play a game with a human. The human would try to pick heads or tails in an unpredictable way, and the machine, with only the knowledge of the person’s last few choices, would try to anticipate the person’s choice and match it. Lucky notes that the computer was able to match the heads or tails choice of the human 5,218 times out of 9,795 plays—the probability of the machine having such success by random guessing is less than one out of 10 billion!

What You Can Do

The next time you play, see if you can figure out where your opponent will serve next. Does your opponent serve to the same place every time? Some do! Does your opponent change targets when down in the game? Or only when up? Or doe he change targets after you've just hit a great return? Try to figure out how your opponent responds to certain situations. You will be like a poker player trying to figure out your opponent with the benefit of being able to hit your best returns more often.

You can also improve your unpredictability as a server. The first way to do this is to improve your ability to hit to any area of the service box. If you are not able to move your serve around the service box, make this your goal, at least on the first serve.

Just to be able to vary your placements will be a major improvement in your game. There are a number of ways to work on serving placements such as aiming for the corners or dividing the service box into zones and aiming for a zone, but in general, for the sake of simplicity, you will at least want to be able to target your opponent’s forehand and backhand, and as you improve, you will also be able to serve right at your opponent’s body as well. As a side note, the serve at an opponent’s body is highly underutilized, especially in pressure situations: serves to the forehand or the backhand run the risk of going wide in one direction or another, but a serve at the body is still in even if it is 2 feet wide in either direction of its intended target.

In addition to being able to vary your placements, it is also useful for your unpredictability to improve your skill with spins. Sidespin, topspin, and kick serves all give you more variety with which you can make your serve less predictable. You can also try using various speeds through the air—very slow serves do not work very often at the higher levels, but a serve that is slower than your normal serve can be very effective. Just like in baseball, an occasional off-speed shot can give your opponent something to think about.

Another way to give your opponent something to think about is to serve and volley. Depending on the level of your net game, following your serve to the net may force your opponent to come up with more than just getting the ball in. No matter what, serving and volleying occasionally could be another surprise that reduces your predictability.

Most people make the predictable play because that is what they are most comfortable doing. So becoming less predictable might not help you if you only play one person and you always win using the same plays over and over again. If you play a variety of opponents and you are eager to improve, however, becoming less predictable can only help you. In the short term, you will learn to prevent your opponent from anticipating what you will do making it harder for her to line up her best shot, and in the long term you will develop new options.