Zak Keasey injured his arm in yesterday's loss to the Eagles and the 49ers announced he will be going on Injured Reserve. He hasn't been placed there yet, but it will happen once they decide how to fill his roster spot.
Keasey injured his arm early in the game, which led to a big increase in Michael Robinson playing time. Given his performance at times, this could end up being a good thing for the offense, although certainly bad for Keasey. Keasey apparently tore a biceps tendon.
The 49ers have numerous options to plug in at fullback including Michael Robinson, Billy Bajema and Delanie Walker. Of the three, Bajema would probably be the best in terms of the traditional blocking concerns of a fullback. Robinson and Walker can certainly block, but they would appear to bring more to the table in terms of actually moving the ball on their own.
The 49ers currently have two players they can stick on the IR in Keasey and Shawntae Spencer. They were waiting to move Spencer because there was no immediate need on the roster for a spot. I'm curious to see what they add now that Keasey has also gone down.