ORCHARD PARK, N.Y. (AP) -Buffalo Bills starting defensive tackle Marcus Stroud has been ruled out at Jacksonville this weekend because of a knee injury.

With Kyle Williams listed as questionable by interim head coach Perry Fewell on Friday because of a sprained knee, the Bills' porous run defense could be missing both starting tackles in preparing to face one of the NFL's most potent rushing teams.

Except to refer to Stroud as day to day, Fewell wouldn't divulge the nature of the injury after the player missed practice for a third straight day. Williams has missed two games, and practiced sparingly this week.

The Bills (3-6) have only two other defensive tackles on their roster, reserves Spencer Johnson and John McCargo.