ORCHARD PARK, N.Y. -- With Derek Anderson recovering from a concussion, the Buffalo Bills are expected to start Nathan Peterman at quarterback against the Chicago Bears, sources told ESPN's Adam Schefter on Tuesday.
Bills coach Sean McDermott said Tuesday that Anderson was in the concussion protocol but did not rule out him playing Sunday.
"We'll see where things stand as we go through the week with Derek," McDermott said. "Then we'll take it from there."
McDermott ruled out rookie quarterback Josh Allen for Sunday's game, meaning he will miss his third consecutive contest after spraining his right elbow in an Oct. 14 loss to the Houston Texans. McDermott said Allen remains week-to-week and is "making good progress" in his recovery but has yet to resume throwing.
Anderson was escorted off the field after he was sacked by New England Patriots linebacker Kyle Van Noy with 1:25 remaining in the Bills' 25-6 loss Monday night. Anderson completed 22 of 39 passes for 290 yards but threw a fourth-quarter interception to Patriots safety Devin McCourty that was returned 84 yards for a touchdown.
Peterman has started three games since the Bills selected him in the fifth round of the 2017 draft. He has thrown seven interceptions in those games and his 16.8 passer rating in starts ranks last among all NFL quarterbacks to have started since last season.
Overall, Peterman has thrown 10 interceptions on 84 pass attempts in eight appearances, including playoffs. Peterman replaced an injured Allen against the Texans, throwing a go-ahead touchdown before he threw two interceptions, including one returned for a score, to lose the game.
"We're going to support Nathan if, in fact, he is called upon to play," McDermott said. "We're going to support him with everything we've got and we expect him to go out and execute, and execute at a high level."
The Bills' 2-6 record is their worst start since 2010, when they began 0-8. They have a 0.1 percent chance to make the playoffs, according to ESPN's Football Power Index.
The injuries to Anderson and Allen leave Peterman as the only healthy Bills quarterback. McDermott said Tuesday that he and general manager Brandon Beane were "looking at" whether they need to sign another quarterback.
The Bills also made official their signing of free-agent wide receiver Terrelle Pryor, who visited with the team Monday.
McDermott did not want to say whether Pryor, a former quarterback, would be a candidate to serve as Peterman's backup Sunday.
The Bills did not make any trades before Tuesday's deadline despite speculation that running back LeSean McCoy or wide receiver Kelvin Benjamin could be dealt.