The New Magic Numbers

Craig O'Shannessy

What do statistics really say about tennis? We are all familiar with numbers like first serve percentages, winners, and unforced errors. But what do those really tell us about who wins, and especially, how to develop a winning game for yourself?

Not as much as many coaches and commentators think. In this series of articles, I am going to help you learn to think another way about the game, not just the pro game, but the game at all levels, and do that by first introducing some different statistics.

These are the new magic numbers. They form a basis for changing the way you think about your match play and especially how you practice.

In subsequent articles I'll relate these insights directly to the development process for all levels. I believe that this new perspective should 100% dictate what happens on the practice court.

These statistics were developed by study of the game at the elite pro level, but also, by looking at the similar numbers across the entire spectrum of competitive tennis, from college to the 18 and under juniors all the way down to 12 and unders and even the 10s. What is most surprising is their consistency regardless of age or ability.

The First Magic Number

The first insight from this research? One percent matters. One point matters. The game of tennis is played with unbelievably thin margins. The difference between winning and losing is shockingly small.

In any given match it can be one or two points. When Novak Djokovic defeated Roger Federer in the finals of the U.S. Open in 2015, the two played a total of 192 points. Federer won 145. Novak won 147.

That was one match. But over the course of a career what percentage of your points do you have to win to be number one in the world like Novak? What percentage of total points played does Novak Djokovic win on average?

I've asked that question to many knowledgeable coaches and sometimes receive answers of two thirds or higher. But the real number? 55%. Slightly more than half.

We take 50/50, tip it just a little and you are number one in the world. That’s it. That's Novak. And it was Rafael Nadal before him and Roger Federer before that.

How does that compare to number two? Andy Murray has won 52% of his career points. John Isner has won 51% and that makes him number 17. Kevin Anderson has won 50% and that makes him number 20.

So if a junior player asks "How do I become number one in the world?" the answer is simple. Go out tomorrow and win 55% of your points in your next match, and keep doing that at every level for the rest of your career, and if you do, eventually you will be number one in the world.

And for the women it's exactly the same. Throughout her career Serena has won 55% of her points. Petra Kivitova has won 52% and she is number 12. Sloane Stephens has won 49% and that makes her number 19. There's the percentage difference between being the greatest player of all time and being on the margins of the top ten.

Look at another example. Who is the most dominant player in the history of game at a single Grand Slam event? Rafael Nadal on clay in Paris. He won the event the first time he ever played it. He won it 9 out of 10 times. He lost one match in 10 years. That means he won 99% of his matches.

What percentage of points did he win in the most dominant run our sport has ever seen? He won 56% of his points.

The first magic number in our sport is the number 55. No other statistic else comes close. If you win 55% of your points on tour you are number one in the world. Up that just one percent and you are Rafael Nadal and a legend in Paris. The tennis world needs to know these numbers!

Rally Length

The second magic number is even harder to believe, much harder. Average rally length.

Despite the universal perception to the contrary, the percentage of ultra long rallies in pro tennis in almost infinitesimal. At the French Open in 2014 I studied over 26,000 total points. Only 24 points in the whole tournament exceeded 27 shots. That is less than a tenth of one percent.

Sound insane? Let's look at the Australian Open final in 2015, the grueling baseline war in which Novak Djokovic defeated Andy Murray in 4 sets. The average point length was 6.8 hits. And that was about one hit longer than the average for all the men's matches in the tournament, with the average at 5.5 hits per point.

In the Djokovic Murray match, about three fourths of the points where over within 9 shots. Only about a a quarter were 10 hits or more. You may think that you are seeing endless rallies. Those are the points you may remember, but the numbers tell a different story.

When we look at overall tour matches, the duration of the points is even shorter. Seventy percent of the points in pro tennis game end within four shots. Over. Done. This means that seventy percent of tennis points are what I call first strike points. A serve. A serve and a return. A serve and a return and one or two more shots. More on this in future articles.

Errors

The third magic number is the percentage of errors. In 2015 at the U.S. Open 64% of all points in the men's draw were errors. For the women, it was 67%.

The simple fact is that only about one third of all points in pro tennis end in winners. The rest of the points are decided by forced and unforced errors.

But what is truly stunning is that we see the exact same magic percentage at all levels of the game, in college tennis, and in junior tennis. Two thirds errors and one third winners.

Most junior coaches would say that can't possibly be right. But there were 30,000 college and junior points in this data set. College errors were 67%. The girls 14’s nationals, U.S. and Canada, was 67%. The girls 12’s was 67%. Amazingly, it's all the same.

Approaching the Net

The fourth magic number has to do with points won approaching the net. Conventional wisdom says you cannot win at the net in the pro game. The speed and the spin on the passing shots are too formidable.

And it's true the number of approaches is limited to a small percentage of points. But is that because those approaches are ineffective?

Again, the numbers say something entirely different. What if I told you that you could win two thirds of all points by going in?

Let's look at the pros first. The percentage of points won on approaches at the U.S. Open in 2015 was 65%.

And another amazing statistic, on overall approaches to the backhand the winning percentage is even higher--over 70%. We'll have more to say about that in this series.

As with the other statistics, the shocking thing is that they apply in college and junior tennis as well. I know this from studying over 80,000 individual points.

If we look at junior boys from the 12's all the way up through men's college tennis, the percentage of points won at the net is almost exactly 60% at every level.

And the girls? Virtually identical. Even in the 12's, girls still win 56% of their points when they approach. By the time they reach college, the percentage is 63%, even higher than male college players.

The Conclusion?

In general our understanding of how points are really won at all levels is not based on reality. These fundamental misunderstandings lead to misguided play, and especially, to misguided practice.

The practice court is broken! So let's fix it. In the upcoming articles in this series, we'll look at how to re-conceive your understanding of the game, how you practice, and especially, how to apply all this to win matches.