Niners bench struggling O'Sullivan

Posted by ESPN.com's Mike Sando

Shaun Hill is working at quarterback for the 49ers after Seahawks defensive back Josh Wilson picked off J.T. O'Sullivan and returned the ball for a touchdown.

I'll be interested in seeing how the 49ers explain the move. Offensive coordinator Mike Martz had been adamant about sticking with O'Sullivan earlier in the season. Was Martz behind the decision Sunday? Or did new interim coach Mike Singletary make the call?

Seattle is running away with this game so far, leading 20-3.