I hate "he ran his socks off".
I also hate it when someone scores a penalty and they say "he sent the keeper the wrong way." No he didn't. The keeper guessed incorrectly. I admit, there are occassions when players accentuate their body position and use their eyes to decieve, but 9 times out of 10, it is a case of the keeper incorrectly guessing which way he was going to shoot.
And it grates me when you hear someone say "he's got a hamstring" when talking about someone who has a hamstring injury. Of course he has a hamstring you plank.
And it annoys me when people say "away goals count double." Err... no they don't. If the first leg is 0-0 and the second leg is 2-1 to the home team, the aggregate score is not 2-2.
And don't get me started on "110%". Grrrrrrr!