First off, this prompt is ridiculous because I would never be on a team that is down by 5 goals unless we were purposefully losing. And maybe that's the case here. Maybe the players got so bored they wanted to lose so badly that fighting would be considered an acceptable thing. It's frowned upon to fight when whooping someone. All that said, I would absolutely be the one to get in the fight. I'm a 6'4" 245lbs tank of a defender with a history of a mean streak. Just look up the videos of me beating up the Wazzu Cougar. I start off with some small jabs, feeling my way around my opponent. Once I know his weakness, I strike with a vicious left hook, right uppercut combo. The loser drops like a sack of potatoes, but I don't stop. I jump on him with an old fashioned People's Elbow followed by a few jabs to the jaw. He's out cold and I'm the victor.