Nate Newton made an alarming observation about that play. Even though Ryan Cook is 6-6, 325 lbs, he got pushed back into Felix by LB Keith Rivers, who is 6-2, 235 lbs. So despite a nearly 100 lb weight advantage, he got steamrolled.
http://www.youtube.com/watch?v=4Pfkk9dazk8&feature=youtu.be