The serve is a technically difficult shot, but that doesn’t mean you can’t master it. Below are five critical insights that aren’t immediately obvious when you start your serving journey. Internalize them, and it will greatly simplify your learning process.
1. Don’t throw at the target.
The tennis serve is not identical to a throw, but the misunderstanding that a tennis serve is not fundamentally a throwing motion (which it is), is often fueled by one of the small differences between the two:
Serving is throwing, but serving at a target is not throwing at a target.
The serve is an upward throwing motion.
This is easiest to experiment with from the service line. To serve into the deuce side box, pretend to throw your racket over the ad-side service box. From the bottom of your trophy pose, explode into that throw, and then feel your shoulder whip through at the top. When done correctly, that shoulder whip will send the ball to the left of wherever your initial throwing vector was aimed (for a right-handed player).
For a full explanation of exactly how to find the shoulder whip that we connect to our upward throwing motion, here’s a full video.
2. 90-90 Preparation
The 90-90 idea is common in baseball, but for whatever reason, tennis players don’t always learn it. Funny enough, the best female player in the world actually doesn’t use it (to start, she gets into it later in the swing).
You should, though. Keep your elbow joint at 90o, and keep the humerus (your upper arm bone) in line with your shoulders, perpendicular to your torso.
This alignment, where the hitting arm is in line with the shoulders, is the biomechanical position we need in order for our third tip – axial rotation – to safely and efficiently generate high velocity.
Use the muscles around your scapula (your shoulder blade) to “connect” your elbow to your torso. Lock it in – down and back – into that 90-90 position, and when the torso explosively rotates, the elbow will naturally rotate with it.
3. Axial Rotation
Throwing rotation occurs perpendicular to the axis of the spine.
Imagine a point on each of your shoulders. As you rotate, those points are going to draw a circle in the air. Your shoulder line should be the diameter of that circle, and your spine will point up through its center.
Since the serve is an upward throwing motion, you are going to be tilted – hitting shoulder above non-hitting shoulder – such that when you rotate, your racket hand is flung upwards.
If you struggle with coordinating that initial explosion, work on this axial rotation. Internalize that swinging up to the ball means engaging your core muscles, adopting a balanced, stable core posture, and then violently twisting around. Since you’ve used your upper back muscles to attach your elbow to your torso, this rotation is going to accelerate your arm quickly and safely.
The better your posture while rotating, the more efficient your rotation is going to be, and the faster your racket will go.
4. Long is good.
If Ash Barty contacted her serve in the image shown here, rather than a few fractions of a second later, she’d sail the ball out past the baseline. This means that if you yourself sail a ball out past the baseline, there’s a decent chance your fundamental motion is fine. The corrective tweak to bring the ball down into the box is small.
Toss
What if Ash had tossed the ball such that, when she reached this point in her swing, she was contacting it? Well, she’d hit it long, or she’d have to contort her swing to drive the ball down, killing her velocity.
Tossing the ball sufficiently far forward is necessary such that, when the racket is striking the ball, it’s on slapping towards the box part of its trajectory.
This will vary depending on the type of serve you’re hitting, but, in general, if you hit a few serves long, try the same motion with a farther forward toss, before making larger changes to your motion.
Timing
There exists a point during the swing at which the racket is aiming towards the box. If you are hitting long, that point is later in the swing than your contact point. Start your rotational explosion a little earlier, or execute it faster. You need to be deeper into your motion by the time you strike the ball.
The primary pitfall I see students run into, when self-correcting their long serves, is that they interfere with the efficient motion they’ve developed. Thinking it’s not “down” enough, they try to volitionally “snap down” using the hand and forearm muscles, thereby breaking the efficiency of the chain.
For most students I’ve worked with, the “snap” internalization doesn’t work at all. I’ve heard it countless times:
“They just tell me to snap, but it doesn’t work. I’ll never be able to serve.”
Twist your trunk, and relax your hand. If you’re hitting long, toss farther forward, or twist earlier and faster.
5. Commit with your eyes.
A serve is a much easier interceptive task than, say, a serve return. You know where the ball is going to be, and, if you’re tossing properly, the ball is moving very slowly at the time you strike it.
Because of this, almost all elite servers don’t watch the ball all the way into contact when serving. To do so would put the head in a bit of an unnatural position – it’s much more comfortable to allow the head to rotate with the torso as you explode.
But this doesn’t mean we can’t harness vision to improve our serve. As you’re about to initiate your motion, your gaze should be locked on the ball. Do not allow your gaze to move until you’ve fully committed to your swing.
Maintaining your gaze on your target will improve your motor performance. When throwing a baseball, that target is, well, your throw’s target. In tennis, on the other hand, we’re “throwing” our racket, and thus our “target” for that throw is the ball itself. At the moment you initiate, you’re visualizing flinging your hand past the ball so the racket can strike it towards the box. You have a mental image (or brief movie) of the contact you’re trying to create, and your throwing motion is the means by which you create it.
Then, after you are fully engaged into your swing, you can begin to let your head turn.
I find many students pull both their non-hitting arm, and their eyes, down too early in the service motion. While we don’t have to watch it all the way into contact on the serve, we still need to fully initiate our swing before we allow our gaze to shift.