This one technically happened on the field, but it still makes our list as it didn't happen during game action. Looking to celebrate Wes Helms's walk-off single in 2010, Florida Marlins outfielder Chris Coghlan tore the meniscus in his left knee while attempting to pie his teammate in the face during a post-game interview.
Coghlan maintains that the injury occurred when he jumped up to complete the prank, but we know what really happened. In the middle of his air attack, Coghlan decided he wanted to eat the pie himself, so he tried to stop his forward movement. He landed on his leg funny, and voila!, another freak injury. We see right through you, Chris.