If you don't know him then you have nothing to lose, just ask him out for a cup of coffee or a beer or something, if you're sure he's playing for the same team. No need to mention the word 'date' either.

That's how my brain works anyway. I have no problem asking out people I don't know, but the more I get to know them, the harder it will be to ask them out. Maybe it's the friend-zone thing.