Bills' Anderson out vs. Bears, Peterman to start at QB

Buffalo Bills quarterback Derek Anderson has been officially ruled out for the team's Week 9 game against the Chicago Bears with a concussion, the team announced.

With Anderson out, the Bills will go back to Week 1 starter Nathan Peterman, head coach Sean McDermott said Friday.

Anderson started Buffalo's Week 8 loss to the New England Patriots but was knocked out of the game with 1:25 remaining in the fourth quarter after taking a sack.

McDermott said Tuesday that rookie Josh Allen is "making good progress," but is still considered week to week with an elbow injury.

Peterman was named the Bills' starting quarterback prior to Week 1 but was quickly benched in favor of Allen. He's completed 40.6 percent of his passes this season, throwing one touchdown and four interceptions.

Rookie linebacker Tremaine Edmunds was also ruled out with a concussion for the team's Week 9 tilt.