From the NFL Rulebook:
ILLEGAL CONTACT BEYOND FIVE-YARD ZONE
Beyond the five-yard zone, if the player who receives the snap remains in the pocket with the ball, a defender may use his hands or arms only to defend or protect himself against impending contact caused by a receiver. If the receiver attempts to evade the defender, the defender cannot chuck him, or extend an arm(s) to cut off or hook him, causing contact that redirects, restricts, or impedes the receiver in any way.
I'm not a fan of this rule, for a variety of reasons. And I don't care for all the whining of Jim Harbaugh, Crabtree, et. al.
But I have no respect for officials that swallow their whistles late in games.
