How to hit flat, slice and kick serves

One swing, three balls. Tilt the axis and the bounce changes.

Traced from real footage

See it, eight instants at a time.

Every frame is traced from real match footage, so you see the shape of the stroke, not a drawing of an idea.

Kyrgios's serve, instant 1 of 8 — Kyrgios's serve: eight instants traced from the footage, frame for frame. Hover or tap to flip.

Kyrgios's serve: eight instants traced from the footage, frame for frame. Hover or tap to flip.

Key facts

~10–30°
A kick serve's spin axis sits about 10–30° off vertical, so it's mostly sidespin, with total spin of 3,200–4,500 rpm.
Tennis Warehouse University, Physics of the Tennis Kick Serve
~5°
At contact on a kick serve the racquet rises only about 5°, against about 30° for a topspin groundstroke.
Tennis Warehouse University, Physics of the Tennis Kick Serve
03
A kick serve crosses the baseline at 5–6 ft.
Tennis Warehouse University, Physics of the Tennis Kick Serve
04
After the bounce the court supplies the upward rebound while the topspin force keeps pulling the ball down, so "more topspin means a higher bounce" isn't a safe rule.
Cross, The kick serve in tennis

Why it works

Spin is the Magnus force with a direction. The topspin part pushes the ball down, so you can clear the net by more and still land it. The sidespin part curves it. Tilting the spin axis is how one swing makes three different balls.

After the bounce the court supplies the upward rebound, and the spin force keeps pulling down during the next flight. What happened before contact helped set the rebound, and the forces after it keep changing the path. That's the kick-serve paradox: a ball that pulls down still jumps up.

Nothing else about the motion needs to change: contact stays at the top of your reach with the arm straight. Only the racquet's path through the ball changes, and that's the disguise.

The line to say on court
“Same swing. Different clock hand.”

Drill: The clock

12 min · alone

Put a marker on the back fence at your shoulder height and take a basket of balls.
Hit ten flat serves to the deuce T, brushing from 6 to 12.
Hit ten slice serves to the deuce wide corner, brushing around the outside of the ball.
Hit ten kick serves to the ad backhand corner, brushing from 7 to 1. Count the bounces that pass the marker.

Number to beat6 of 10 kick serves bouncing above the shoulder marker

More drills like this: serve, practise alone

Faults and fixes

Kick tossed in front

Without an arch, the brush can't go up and across.

FixToss over your head.

Pancake face on the flat serve

Turning the face early kills the turn through the ball.

FixDrop the racquet edge-on and turn late.

Slice from the wrist

You twist the face instead of brushing the outside.

FixBrush around the ball with the arm and keep the face quiet.

Kick hit at full pace

Speed steals brush, so the ball skids instead of climbing.

FixUse a slower arm and a faster brush. The fence marker keeps you honest.

Questions players ask

Which second serve should I hit to a right-hander's backhand from the ad court?

Usually the kick. It climbs into the backhand shoulder they don't want it on. A right-hander's slice wide from the ad side tends to curve toward their forehand, and a flat serve has the lowest margin.

Is a kick serve topspin?

Mostly sidespin. Its axis sits about 10–30° off vertical, with a topspin part that pulls it down over the net.

Why does my kick serve skid instead of jumping?

You're probably hitting it at full pace, and speed steals brush. Use a slower arm and a faster brush.

How do you disguise your serve?

Keep the motion the same and change only where the strings brush the ball: 6 to 12, around the outside, or 7 to 1.

What this doesn't cover

The spin and bounce numbers here are for the kick serve only. Reliable ranges for flat and slice spin, their bounce heights and kick serve speeds still need sourcing. Ball-flight model heights are illustrations, not predictions for any serve, and spin can't be read from ordinary video. Placement advice assumes a right-handed server.

Sources

Tennis Warehouse University, Physics of the Tennis Kick Serve
Cross, The kick serve in tennis

Serve and returnHow to toss the ball for a tennis serveToss from a straight, locked arm, release at eye level, and send the ball to the same spot every time. For a right-hander, the flat serve's toss sits slightly in front and to the right, slice further right, kick further over the head. The toss sets contact height, spin and placement before you swing, so fix a wobbly serve at the hand first.Serve and returnHow to hit a reliable second serve under pressureUse a familiar second serve at a comfortable, repeatable effort to a broad target. Keep the brush you have practised; full brush does not mean maximum effort. Slowing the action changes both pace and spin, and net clearance alone does not settle the trade. Judge both whether it lands and what happens in the point. Second-serve points won includes double faults; a rate calculated only on serves that land answers a different question.Serve and returnHow to serve in tennis: the service motion step by stepBuild the serve through coordinated leg, trunk and arm movement. Compare your loading, racquet drop, contact and landing with a coach. Published energy and racquet-speed contributions describe different quantities; they cannot be added or used to predict your speed gain.StrikeHow topspin works: the Magnus effect in tennisTopspin changes the airflow around a tennis ball and produces a force that bends its flight downward. At fixed launch speed, angle and height, added downward lift brings the ball down sooner. To turn that dip into greater net clearance, choose a higher launch angle as well.