Jason Campbell's left knee improving

ALAMEDA, Calif. -- Jason Campbell's injured left knee is improving and he is expected to be able to start this weekend against Denver if he has no setbacks.

Coach Tom Cable said the final decision on whether Campbell can start against the Broncos on Sunday will likely be made just before game time. Kyle Boller will probably start if Campbell can't go.

Starter Bruce Gradkowski's injured right shoulder is improving but Cable says it is "very questionable" if he can play this week,

In other injury news, Cable says running backs Darren McFadden and Michael Bennett are likely to play after missing last week's game with hamstring injuries.

Safeties Tyvon Branch and Hiram Eugene are questionable with sore backs. Backup tight end Brandon Myers is questionable with a concussion.