Redskins coach Jay Gruden says linebacker Brian Orakpo is done for the season because of a torn right pectoral muscle.
Gruden says Monday that Orakpo needs surgery.
Orakpo, a three-time Pro Bowl selection, was hurt trying to make a tackle on a running play early in the fourth quarter of Washington's 19-17 victory over the Tennessee Titans on Sunday.
Orakpo twice has torn the pectoral muscle near his left shoulder in the past.
He had a half sack for the Redskins (2-5) this season.
Gruden says rookie linebacker Trent Murphy, a second-round pick out of Stanford, will start in Orakpo's spot and is "going to have to grow up very fast."
Washington plays at the Dallas Cowboys next Monday night.
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