Gideon hadn't quite figured out that he was the one most invested in the game. "That's not my reason," he protested, looking indignant even as he tossed himself into the water towards Sirius in a passionate attempt to tackle him. "Not everyone's a dog like you Sirius," he joked, the pun of his words completely escaping him, "Some of us are gentlemen."
With that, he reached around and tried to grab the ball out of Sirius' hands, or at least knock it out of them so that Dylan could swim up and pluck it out of the water. It was silly, sometimes, how competitiveness could make him so singularly minded. When he finally realized how much more seriously he was taking the game compared to everyone else, no doubt he would ease up. As it was, he was going all out. It was an inescapable fate--he always had been the type to throw himself wholeheartedly into any sport he decided he was going to play.
He waved his arm in front of Sirius, trying at the very least to deflect his throw to Glee, if attempts at hitting the ball out of his hand didn't work out as planned.