Lewis, a 17-year pro and 13-time Pro Bowl selection, will be shelved for the remainder of the season with a complete tear of his triceps muscle following Sunday's 31-29 win against the Dallas Cowboys, Ravens Coach John Harbaugh said.
Lewis had racked up 57 tackles and one sack in six games this season.
Webb, meanwhile, was diagnosed with a torn anterior cruciate ligament in his left knee -- also sustained during Sunday's game.
Webb, a fourth-year pro, finishes the season with 25 tackles and one interception after signing a $50 million, six-year contract in April.
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