Willis was placed on the season-ending injured reserve list Tuesday for the injury suffered in the third quarter at St. Louis on Oct. 13.
"It's very frustrating," Willis said. "My teammates mean everything to me and I want to be out there experiencing all the good times and all the rough times with them."
A Pro Bowler all seven seasons in the
As Willis goes on the IR, the 49ers are expected to have linebacker
Smith is set to begin practicing this week after serving a nine-game suspension by the NFL for violations of the league's substance-abuse and personal-conduct policies.
In addition, 2013 All-Pro linebacker
Bowman is recovering from surgery on his left knee after he tore the anterior cruciate and medial collateral ligaments in a devastating injury in the
Mebane's loss is a blow to Seattle's run defense, which ranks fourth in the league at 79.8 yards per game.
The Chicago Bears waived former
The receiver signed a one-year deal with Chicago in August after being released by the
The Dallas defensive tackle was activated Tuesday, a day after the end of a 10-game suspension imposed by the NFL when he was reinstated before the season.