Recording Errors

If players want to improve, they have to know about their errors. Tennis has always made this process very confusing by only reporting on unforced errors, rather than the difference between forced and unforced. Rather than muddy those waters further, let’s try to make it simpler.

In this article, I’ll be using examples from international 12 and 13 year old players to, hopefully, make a comparison to your player easier.

First Two Rules

Whenever I’m recording pro analytics, I go by the following two rules for serve and return:

  • If a return is missed on a 1st serve, it’s an unreturnable ie a “1”.
  • If a return is missed on a 2nd serve, it’s a return error ie a “2”.

I use the same mantra when recording junior matches, rather than being too subjective about serve and return. So that part’s easy.

Unreturned 2nd Serve is an Unforced Error by the Returner

Examples of 1

Examples of 2

So, 1s and 2s are easy decisions. While some would argue against the way I do it, there are other ways to measure unreturned 1st serves which could have been recorded as return errors which, in the long run, are much better ways of recording a missed return. More on that later.


Now we get in to the more subjective part of recording analytics. Don’t worry, there’s really no such thing as “getting it wrong” and there are far less difficult ones than you might think. What I like to do with junior matches is think of the difference between forced and unforced errors as reward for good play vs penalty for bad play.

Rather than carry on with words, here are 3 examples of where I thought the play from the attacking player was good enough to reward them with forcing their opponent into error:

The way to record those points is not to count the forced error by the player who is defending. The shot that forced the error is the point ending shot ie by the player who won the point.

So the rally lengths in this sequence were 3, 6 and 4.

Now for the unforced errors where the final shot has to be counted.

So, those rallies were 3, 5, 3 and 6 shots long.

If You're Having Trouble

Don’t worry, help is on the way. We’re holding two online sessions this coming Thursday evening: one at 7.30pm for Eastern States and another one at 7.30pm for those in WA. You should have received an email with instructions on how to register. Numbers will be kept small to allow for questions.