Jannik Sinner had a dominant year on tour going 72-7 and winning two Grand Slam titles. He is one of the best players in the world at controlling what he is able to control. Contributing to his success, Sinner held serve in the 2024 season at a higher rate than anyone else on the ATP Tour, winning 91.4% of all service games (according to Tennis Abstract). How do you try to level the playing field against an elite server? You hold serve.

Perhaps there was no better example of Sinner’s dominance this season than his US Open run in which he only dropped two sets the entire event. Looking at his matches from the round of 16 onward, Sinner’s opponents had tremendous success when they varied their first serve speed up or down.

 

Looking at the breakdown of first serve winning percentages by opponent, we see that, while not every opponent had success varying their speed up and down, each opponent was able to raise their win percentage by at least 10% in one of the two categories.

Mixing up pace can be a tremendous tactic for many reasons. Notably, when you reduce your serve speed, it can be much easier to hit your targets. Let’s look at how often wide spot targets are hit based on serve speed:

There is a massive gulf in ability to hit your wide serve spots based on your serve speed. Slowing down your serve allows you to home in on your target and speeding up your serve allows more margin of error on your targets.

Below, we can all the deuce side first serve locations hit in the “slow” and “average” zones.

On the left are all the first serves hit that were at least 5% slower than that player’s average MPH. On the right are all the first serves that were hit between 5% higher and lower than that player’s average MPH.

Looking at this, we see a cluster of winning points off serves hit shorter in the box that pulled Sinner off the court. This pattern of slowing down your first serve to pull Sinner wide then open up the court was very success – particularly for Tommy Paul who used this as a bread-and-butter pattern against Sinner.

Another benefit of varying your serve speed can be simply throwing off your opponent’s timing. If we compare high serve speeds versus average on the deuce side, we see a very apparent pattern.

On the left are all the first serves hit that were at least 5% faster than that player’s average MPH. On the right are all the first serves that were hit between 5% higher and lower than that player’s average MPH.

Nearly all of the faster serves are hit to the T to try and attack Sinner’s backhand. We see a very clear winning pattern doing so; whereas hitting that same target in the opponent’s average serve speed zone yields a much lower winning percentage. We saw before that lowering your serve speed can make hitting targets easier, now we see that hitting your serve faster can counteract missing those same targets.

Next time you or your player go out for a match, look out for their serve speed variability and see if these trends continue for you.