The San Francisco 49ers have gotten pressure on Carson Palmer all day long, and they are somehow getting railroaded by the referees. Quinton Dial got to Palmer in the fourth quarter and made what appeared to be a big sack. Instead, the referees flagged Dial for roughing the passer. As you can see in the video above, Dial drove into Palmer's chest for pretty much perfect technique on the sack.
The only thing I can think is the referees saw Palmer's helmet pop up and assumed it was a helmet-to-helmet it. This is the exact reason instant replay is necessary for these kinds of plays.