The first-round draft pick practiced fully Monday, and says he is preparing to play Sunday, when Buffalo opens the season at Chicago.
Watkins declined to reveal the nature of the injury except to say follow-up tests showed it is something more than bruised ribs.
He was initially hurt in the first quarter of a 19-16 preseason loss at Pittsburgh on Aug. 16. After sitting out one game, Watkins was hit in the same spot in the first quarter of a 23-0 preseason-ending loss to Detroit on Thursday.
Tight end Lee Smith (toe) and linebacker Randell Johnson (ankle) did not practice Monday.
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