Redskins rule out Portis for Sunday

From the Associated Press:

ASHBURN, Va. -- Washington Redskins running back Clinton Portis has been ruled out for Sunday's game against the Denver Broncos.

Portis sustained a concussion in last week's loss to Atlanta and was not at the Redskins practice facility Thursday. Coach Jim Zorn said Portis was home on "doctor's orders."

Portis' backup, Ladell Betts, is nursing a sprained ankle but is expected to play.

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