Denver Broncos DT Kevin Vickerson took an ugly cheap shot at Samson Satele that forced Satele to leave the game. While kicking the extra point following a Colts touchdown, Vickerson can be seen going low, then raising his arm and dropping it on Satele's already injured leg (he had left the game earlier).
Satele then writhed in pain in the end zone before pointing out Vickerson to head coach Chuck Pagano as he was helped off the field.
Vickerson is the NFL's third-most penalized player already and didn't even get caught for this one. The NFL will likely fine Vickerson since there's footage of this.
Hat tip to The Big Lead for the find.