I don’t play soccer because I enjoy the sport. I’m just doing it for kicks.
Why this joke works
A Phrase Already on the Field
“For kicks” usually means doing something for amusement, while soccer supplies literal kicks. Read the first sentence sincerely, then let the second sound like a small confession. The ordinary phrasing is what makes the sports meaning arrive cleanly without extra setup. Soccer is played mainly by kicking the ball, so the casual expression also clearly describes the sport’s basic action.
A closer look
A Familiar Motive Is Literal on the Soccer Field
“Doing it for kicks” usually means acting only for amusement, without a serious purpose. Soccer makes that motive physical because kicking is central to moving and shooting the ball. The first sentence denies enjoyment, apparently setting up a sincere explanation; the second gives an expression that secretly puts enjoyment back in. That small contradiction makes the line more than a simple sports definition.
Fact behind the joke
Handling the Ball Is Usually a Foul
FIFA’s Laws of the Game say a direct free kick is awarded for deliberately handling the ball, with a goalkeeper exception inside that player’s own penalty area. Most players therefore advance and control the ball chiefly with feet, legs, torso, and head. Kicking is not the sport’s only skill, but it is common enough to make “for kicks” instantly fit soccer.