Williams practiced for a third straight day on Friday and is listed as probable for the Ravens after missing the last two games with a hamstring injury.
Backup Jonathan Stewart attempted to practice Friday with a sprained knee but Rivera didn't sound optimistic about his chances of playing, saying ''he didn't have what he needed as a running back.'' Stewart is listed as questionable.
Third-string running back Fozzy Whittaker (hamstring) is doubtful.
If Stewart and Whittaker are inactive, Darrin Reaves would serve as Williams' primary backup.
Rivera said outside linebacker Thomas (hip) looked good in practice, but will be a game-time decision.
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