Kawika Mitchell misses practice

ORCHARD PARK, N.Y. -- Buffalo Bills middle linebacker Kawika Mitchell missed practice Thursday because of a foot injury and it's doubtful he'll play in the season opener against Miami on Sunday.

Coach Chan Gailey declined to say which foot Mitchell injured, or to release details except to say he was hurt in practice a day earlier and is "doubtful" to play. Mitchell was having tests to determine what Gailey called a "short-term and long-term" prognosis, an indication the injury could be severe.

Mitchell, a seven-year NFL veteran, is a backup to Andra Davis, who's taken over the defensive play-calling duties this season.

Mitchell is coming back after he missed the final 11 games last season with a right knee injury.

The Bills are already expected to be without outside linebacker Reggie Torbor, who's recovering from a chest injury. Converted defensive end Chris Ellis is expected to start in place of Torbor.

Gailey was optimistic starting safety Jairus Byrd will play after missing nearly a month after having groin surgery. "He was out there and moved around really well today at practice. It's an improvement over yesterday," Gailey said.

Byrd earned a Pro Bowl selection as a rookie last year after finishing tied for the NFL lead with nine interceptions.