Rivers did not practice all week after suffering the injury in the third quarter of Buffalo's Week 1 win over Chicago. He made four tackles before leaving the game against the Bears.
The return of linebacker Nigel Bradham should offset the loss of Rivers. Bradham, one of Buffalo's most improved players from a year ago, missed Week 1 because of a suspension. Rookie Preston Brown is also expected to stay in the starting lineup with Rivers out.
Cornerback Stephon Gilmore (groin) is expected to start after missing Week 1. He is listed as probable. Receiver Sammy Watkins (ribs), receiver Chris Hogan (ankle) and safety Aaron Williams (concussion) are also probable. Tight end Lee Smith (toe) and safety Jonathan Meeks (neck) are doubtful.
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