Southern California coach Pete Carroll all but ruled starting tailback Chauncey Washington and backup quarterback Mark Sanchez out of Saturday night’s opener against Idaho.

Washington, a fifth-year senior who led the top-ranked Trojans in rushing last year with 744 yards on 157 carries, has a sprained right shoulder, and Sanchez has a cracked bone in his throwing thumb.

“Chauncey’s not ready to go yet. It’s not likely he’ll be ready to go this week,” Carroll said after practice Monday.