The crowd, the trash talk, the scoreboard, that mistake from two minutes ago, your own racing thoughts. Competition is a distraction machine, and telling yourself to "just focus" usually makes it worse. Focus is not effort. It is direction. The skill is choosing what your attention lands on and gently bringing it back when it wanders, which it always will.
The two focus mistakes
Athletes usually lose focus in one of two ways. They aim it at things they cannot control, the ref, the outcome, what people think, or they aim it at their own mechanics and jam a skill that should be automatic. The fix for both is the same: give attention a clear, useful target outside yourself.
How to lock in
Pick your focal point
Before each play, decide the one thing your eyes and mind belong on. The ball. The target. Your check. Narrowing to a single cue is what the "quiet eye" research keeps finding in the best performers: a steady, specific gaze right before action.
Use a reset cue
Your mind will drift. That is not failure, it is normal. The pros are not distraction proof, they are just faster at noticing the drift and returning. Build a two second reset: one breath plus a cue word to snap back to your focal point.
Play in the present tense
Almost all lost focus is time travel. You are in the past replaying a mistake, or in the future worried about the result. Both pull you out of the only play you can actually influence, which is this one. A simple question helps: "What do I need to do right now?"
Train focus like fitness
Attention is a muscle. A few minutes a day of returning your focus, through breathing or a short mindfulness practice, makes it easier to come back mid game. You are literally rehearsing the skill of refocusing.
You will lose focus during every game. Winning the focus battle just means coming back faster than you drift away.