I wonder if something happened at the show that upset him? Maybe not something you consciously did, but something he interpreted in a way that hurt him, and made him feel like the only way to get out of the situation was to simply leave. I have no idea what would cause that, but I know something similar has happened with me and my husband... (Ive made jokes about something that he did not find funny, and in fact offensive for his own personal reasons, and he tends to just shut down at the moment of impact, and will only open up about it later, leaving me extremely bewildered and upset myself until I find out what it was I said, so we can both talk about what happened and both make our apologies).

I agree that the best thing to do would be to talk to him, and try not to be confrontational about it. Don't put him on the defense because that will only make matters worse. I guess my suggestion would be tonight at the hockey practice, mention to him you'd like to talk to him, and would he be free for coffee in the near future? If he says no, well, then it's out of your hands really. Tell him you there to talk whenever he's ready, and just leave it at that. Be polite and friendly when you have to be around him, but don't try to go any further. If he agrees to meet up for coffee (or whatever) just tell him, simply and calmly, that you were really confused about the other night and would just like to hear his perspective of what happened, and the share your perspective. And hopefully you two will be able to come to some sort of understanding and this might help build a stronger relationship for the future, either friendship or romantically.

Good luck! Keep us posted!