CHARLOTTE, N.C. -- Things just keep getting worse for the woeful Carolina Panthers.

The Panthers (1-8) placed running back DeAngelo Williams on season-ending injured reserve on Wednesday with a mid-foot sprain the same day quarterback Jimmy Clausen sat out practice with a concussion.

Coach John Fox says Williams wouldn't have been able to return for two to three weeks and they "needed the roster spot." The Panthers promoted guard C.J. Davis from the practice squad, with starting left guard Travelle Wharton (toe) sitting out practice.

Fox says it's likely rookie Tony Pike or Brian St. Pierre, a journeyman signed to the active roster Tuesday, would start at quarterback for the Panthers Sunday against Baltimore.

Clausen was hurt late in Sunday's 31-16 loss to Tampa Bay.