They say concussion...however, from the article I read it seemed like they were saying he got a concussion from falling on the ice as he did. One could lose consciousness as he did with a concussion, but I still think there may be a heart thing involved...seems too odd. Hope he recovers well. Dehydration, after thinking it over, is probably not the best prediction because pro athlete's (unlike the dummies I deal with daily) are very disciplined about such things. I'm interested to see what the final diagnosis is, but certainly odd.