From here on out, the Bills will be without the services of linebackers Kawika Mitchell and Marcus Buggs.
Both players suffered season-ending knee injuries in Sunday's 6-3 loss to Cleveland and will require surgery, according to ESPN.com.
Buffalo already lost linebacker Paul Posluszny to a broken arm during Week 1's loss to New England. He is still a few weeks away from returning, leaving fourth-year player Keith Ellison as the only experienced linebacker on the squad.
The depleted linebacking corps won't do much for the status of head coach Dick Jauron, whose job has been in jeopardy for much of this young season.
"I understand that criticism," Jauron told ESPN.com. "That's the job. I'm in that position, and I clearly haven't been able to reach [the players] to help them — particularly in these last three games — to get them over the hump to get us where we win."
The 1-4 Bills failed to score a touchdown against Cleveland for the second straight week.