He punched a wall or a locker.
Only thing that makes sense.
Get a little fired up, take it a little too serious and end up hurting themselves.
Holloway wasn’t going to lose to his former school, that’s a promise.
So he’s gotta leave it all in the locker room.
Sure, you got the win, but sitting at a hospital/urgent care late night?
No one wants that.
You know you’re in for a long night and you just want to sleep.
Got the win though, you know that’s all that matters to Holloway.