Redskins' Trent Williams questionable to play Sunday vs. 49ers

Washington Redskins left tackle Trent Williams is officially questionable for Sunday's game against the San Francisco 49ers with a knee injury suffered in the Redskins' loss to the Tampa Bay Buccaneers. 

Williams has reportedly showed some improvement in the training room, but he was unable to practice all week. 

If Williams can't play Sunday, rookie Morgan Moses will likely be asked to fill in. Moses could be in trouble against a 49ers pass rush that is on a roll after the return of Aldon Smith.