Needed: a football helmet and bubble wrap

Isn't volleyball a non-contact sport? How does my daughter get a concussion playing it? Seriously folks, she just plays too hard. Sunday we were at a tournament and she and a teammate dove for a ball. Sam, the teammate, hit her jaw on the back of Morgan's head. Sam went out of the game, Morgan shook her head a few times but continued playing. Then she dove and did a volleyball roll, at which time she hit her head on the floor again. It's a good thing the tournament was called due to another winter storm after our first game. She hasn't been feeling well since!