Here's another good play from Kaep, but, he probably could've gotten more.
Here there running a short out with Vernon, a hitch with Anquan a deep cross with McDonald and a streak with Crabs. The rams start out with a 2 high safety look and just before the snap walk the SS down
When the safety comes down he's dropping into man coverage on Vernon. The Rams are going for a cover 1 blitz. However, I'm pretty sure the 2 TE set confused on of the OLB's on who was the "strong" side. They probably called a "strong side" blitz cause nobody covers McDonald.
Here you see the blitz from the Rams, Kaep does do a good job of understanding that his protection cannot block 1 of the guys coming and watches the defender on that side, not, the receiver.
He sees the safety in a flat footed stance and the corner in a backpedal. Vernon ends up being open because of his speed, but, really the right read is to the hook against a backpedal as the flatfooted defender can make a jump on the ball. Unfortunately, Kaep never sees McDonald break WIDE open due to the defensive breakdown.
Know though, that seeing an all out blitz, he knows he has to get the ball out quick and doesn't have time to scan the field. So, I can't really blame him for that.
Kaep does show good anticipation though in that you can see in this shot he's planted his backfoot and starting to step into his throw. Meaning, he's decided to throw the ball before Boldin turns around. Something he failed to do in the super bowl with Randy Moss running the exact same route.
He gets it out to Boldin for a 9 yd gain. Would've been nice to hit McDonald though, only the free safety anywhere around.