The Pittsburgh Steelers have released quarterback Byron Leftwich so they can dress an additional defensive lineman for Sunday's game at Tennessee. Leftwich is expected to return to the 53-man roster on Monday. He already is guaranteed his full salary this season. With nose tackle Casey Hampton (hamstring) injured, the Steelers were down to two backup defensive lineman. Leftwich's roster spot will be taken by Steve McLendon, a first-year player from Troy State.