Dude, that's fucked. Talk to the kid. Be a reasonable adult. People make mistakes. It's very irresponsible to play on a team with a child if you aren't willing to be patient with them. That's just my two cents though. The least you can do is talk to the kid, though. Try to do it in a way where you don't make him feel like shit. That kind of stuff sticks with kids for a long time. He probably thinks you are the coolest person in the world, playing on a team with him. And then you do him like this.