Quarterback Caleb Hanie was looking to complete a 17 yard pass to Knox, who lost the football due to the hit by rookie safety Kam Chancellor. After the ball was loose, defensive lineman Anthony Hargrove collided with Knox, bending his head and neck in ways they shouldn't have bent, and was particularly uncomfortable to watch. The fumble would result in seven quick points for Marshawn Lynch and the Seahawks.
You can find a link to the hit here, but be warned, it is a gnarly hit, and is most definitely uncomfortable to watch.
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