Athletes are passionate about the game and when they feel that they're being unfairly judged, sometimes verbal warfare (or worse in some cases) breaks lose. Enter Serena Williams. She went in on a chair umpire at the US Open because she felt the umpire was being a "hater" by giving Sam Stosur unnecessary points.

Down one set and facing a break point in the first game of the second, Williams hit a forehand and shouted, “Come on!” as her opponent, Sam Stosur, was swinging at the ball. Chair umpire Eva Asderaki ruled that Williams hindered Stosur’s ability to complete the point and awarded it to Stosur. Williams argued the call and went in on the umpire by calling her a hater and telling her not to come her way if they run into each other in the hallway. Watch:

Props to Bossip.