Source: Mario Williams out indefinitely

Houston Texans linebacker Mario Williams has a torn pectoral muscle that will sideline him indefinitely, if not for the remainder of the season, a person familiar with the injury told ESPN NFL Insider Adam Schefter.

Williams is having more tests Monday to see if there's any hope the Texans could get him back later this season.

Williams appeared to be hurt while sacking Jason Campbell with about five minutes left in the first quarter of Houston's 25-20 loss to Oakland on Sunday.