49ers' Raheem Mostert: Out with forearm injury

Mostert is out for the remainder of Thursday's game against the Raiders with a forearm injury.

Mostert was tripped up in the backfield on a third quarter run and suffered a gruesome looking injury to his forearm. The third-year back headed to the locker room in an air cast and could be looking at an extended absence going forward. Mostert was electrifying before exiting, ripping off multiple big runs including a 52-yard scamper in the third quarter. Matt Breida and Alfred Morris figure to head up the 49ers backfield if Mostert indeed misses game action.