Football is a violent sport but it is very rarely a dirty one. Detroit Lions center Dominic Raiola crossed that line for the worse in a big way this Sunday.

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Raiola was pulling towards the right on a run block when he stomped down hard on the outstretched -- and vulnerable -- ankle of Bears defender Ego Ferguson. While one cannot 100 percent prove the deliberate intent behind Raiola's actions, the clip does him no favors.

Raiola told ESPN after the game that he was "stumbling" on the play and didn't mean to place his foot where he did. However, in the video Raiola clearly seems to be in control and looks down at Ferguson's leg before coming down on it forcefully.

Raiola apologized to him after the game, but "none of that matters," according to Ferguson.

"We all saw the play," he said. "You can't take back what happened with that play. That's the end of that."

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"There's no need for it," concurred Ferguson's teammate, defensive end Jared Allen. "That's our guy's careers here. You can break someone's ankles."

Raiola was fined $10,000 last month for diving at the New England Patriots offensive line as the Pats were taking a knee on the final play of the game. He can now expect an even heftier penalty after yesterday's actions.