49ers' Willis puts KO shot on Hasselbeck

Posted by ESPN.com's Mike Sando

SAN FRANCISCO -- Seattle's Matt Hasselbeck is paying for his competitive nature after 49ers linebacker Patrick Willis drilled him in the back on a run toward the end zone.

Hasselbeck got up, walked toward the sideline and signaled that he would need a replacement. Hasselbeck's legs then went rubbery and he staggered before trainers caught him. He just got up and is walking after being down for a couple of minutes.

Seneca Wallace is in the game with 26 seconds left in the first half. He threw a 1-yard touchdown pass to Julius Jones on his first play. Wallace's mobility is an asset. His presence in the game changes strategy for both teams. Look for some bootlegs.