What wins a tennis match?

With Wimbledon upon us it's time to dust of that old racquet at the back the cupboard and venture out  onto the tarmac of the local park courts. As you sit patiently waiting for someone to finish and the court to become free you begin to imagine hitting glorious forehands and backhands in between screaming aces and delicate drop volleys. The reality of course is rather different as you chase balls around liked a crazed puppy and regularly have to leave the court to fish the ball out of the undergrowth where it disappeared as you skied one over the fence. It's not as easy as it looks on TV.

Tennis is actually a very technical game and to do it well takes skill and practice. A millimetre out at your point of contact with the ball can make a 1.5m difference by the time it lands at the other end of the court, if in fact in lands in the court at all! But once you've learnt the basics and you can serve the ball into the court and rally it can be a lot of fun, and as you develop your skills you will discover the pleasure of hitting the ocassional winner cross-court or down the line as they say. But how many points do you need to win by hitting outright winners? And how many points do you need to win over the course of a match in order to win the match?

Statistically it's surprisingly fewer than you might think. In fact the ATP No 1 over the last 20 odd years usually averages around 55% over the course of a season. Some matches come down to a single point, and there are times when the winner of the match actually wins fewer points than the loser. It's all to do with the way the scoring system works. Whether you win a game "to love" or after four or five deuces doesn't matter when it comes to winning games. It's those points that decide games that are the most important ones to win.

Here's another interesting statistic. Hitting glorious winners is great, but how many points on average are decided by winners? I took a quick look at the stats for three matches at Wimbledon. Here's the data:

Look at the winners as a percentage of total points won. 36, 29 and 14%. A third or fewer of the total points won come from outright winners. So when your coach tells (as mine constantly does) that you need to reduce your error count, they might just be right! There simple truth is that more points are won by forcing an error from your opponent than by hitting winners. It's not a big sample, but it is a pattern most tennis players and coaches will have seen over and over again. 

If this is the case at the highest level of the game then how much more true is it at club and social level? Keeping the ball in play, making fewer errors will probably win you more points and more games and therefore more matches.