The Magic Number One

Craig O'Shannessy

In the first article I gave an overview of what I called the new magic numbers in tennis. Compiled from all the levels of tennis, these numbers included average rally length, the dominant role of errors in determining outcome, and the surprising effectiveness of net approaches. (Click Here.)

This new statistical perspective is turning the way the game is understood and coached upside down. But now let's look at probably the most shocking number of all from this research.

That number is the most common rally length. By that I don't mean the average rally length, but the most common number of times the ball is struck in a point. The most common number of hits.

The question is whether this number is the same, more, or less than the average rally length? I like to ask this question at coaching conventions. Most coaches will say that that the most common number of hits in a point is somewhere between 4 and 6. This I hear even from coaches who are working on the tour.

But what's the real number? One. That's right, one! The highest percentage of points are determined by one hit, when the ball is struck on a serve and it doesn't come back. What percentage? Almost 30% of all points in the men's game are one hit, based on my study at the Australian Open in 2015.

What's the next rally length with the next highest percentage? For the men it's three hit--about 15% of the total points. Three hits means a serve, a return, and one more shot from the server.

Next number? 2 hits. A serve followed by a return. That accounts for about 10% of all points.

And if we look at four hit rallies, they account for another 7.5% of points. In those points the returner wins the point with a return and then one more shot. So add that up. Over 61%--far more than half the points in men's pro tennis--are determined by 4 hits or less.

Wait now, didn't I make the point in the last article that the average rally length was 5 to 6 hits? How could these numbers I am now quoting be less? The key to understanding the numbers is to realize that some percentage of all point go on longer, 8 hits, 10 hits, all the way up to 20 hits and more for a small number of points. That pushes the average up.

But the majority of points won or lost are still determined by 4 hits or less. This table shows the rally length for the men in Australia in 2015, for all rally lengths all the way up to 27 hits—of which there were a total of two!

What About the Women?

You might imagine the women play longer points, but the data for the 2015 Australian Open says differently. For women pros, the total number of points decided by 4 hits or less is actually higher than the men. Over 66% of their points are decided by four shots or less, compared to 61% for the men.

About 27% of the women's points are decided by one hit--a serve. This only slightly less than the men at 29%. About 15% of women's points are decided by two hits—a serve and a return. A little more than 14% are decided by three hits. Another 11% are decided by four.

So add that up and you get two thirds of women's points decided by 4 hits or less—and interestingly, the duration of the longest rallies was also less than the men.

The longest men's rally as we saw was 27 hits. For the women it was 21 hits and that was for exactly one point.

Here is the chart for the women:

What Does this Mean?

What does this mean? And especially what does this mean for the practice court? It means the practice court is broken.

Hitting seven consecutive balls in the court builds consistency. It is critical that we have shot tolerance to be successful in our sport. But how much is too much? When does it become overkill?

Look at it like this way. Hitting seven balls in a row in the court equals a 14 shot rally. A 14 shot rally happens less than one percent of the time in our sport for both the men and the women.

Where do you want to spend your time? On the type of points that comprise one percent of match play, or on the type of points that comprise the majority?

The implication of the evidence is shocking. The evidence clearly shows that our time on the practice court is misguide and not nearly as effective as it needs to be. The problem is we have no balance. We grind and slap groundstrokes around for hours, get exhausted and congratulate ourselves on how hard we are working.

Meanwhile we don't spend anywhere near enough time on the serve and return, the two shots that determine the biggest percentage of points. The shared delusion is that groundstroke rallies are what matter the most. They don't.

In a two set match it's likely you will hit 50 to 100 serves. How many times have you hit anything close to that number in practice? Much less focused on hitting a high percentage of them accurately to target spots?

I recommend spending time working on hitting your spots in both courts on both first and second serves. And on all your spin variations. And charting your ability to do so.

The Return

I also feel players should double, triple, even quadruple their time practicing returns. Again you are going to get a chance to hit dozens of returns in a match.

The statistics show that 10% of all points end with 2 hits, meaning with a return. But the implications of return practice go further. For the men 7.5% of all points end with four hits. And for women that four hit percentage is higher at 11%.

For hits means the returner wins the point by hitting a return and then one other shot. If you don't get the serve in play, you have no chance of winning a four hit point, one of the top four point durations in tennis.

We saw in the first article that winning 55% of all your points makes you number one in the world. So how important is it to win a large number of those points that are 4 hits or less?

Massively important. In fact winning the shorter duration points is the absolute key to winning virtually any match at any level, for the simple reason that they represent the majority of all points played.

Stayed Tuned for More on the New Magic Numbers and what they mean for your game in upcoming articles!