Concussion Sidelines Clinton Portis

As if the slumping Redskins needed any more bad news, running back Clinton Portis left Washington's game in the first quarter after suffering a concussion.

Portis took a couple of hard shots on a running play, with Atlanta's Chevis Jackson and Thomas DeCoud each landing blows -- at least one of which appeared to be helmet-to-helmet. No penalty was called on the play.

Portis stayed down on the field at the end of the play, then walked unsteadily to the sideline. He sat on the Redskins' sideline with a towel over his head while backup running back Ladell Betts replaced him. Jason Campbell threw an interception on the next play that was returned by the Falcons' Tye Hill for a touchdown.

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Portis finished the day with just four yards on four carries.

There was no immediate word about the severity of Portis' concussion, though he did appear to remain conscious and stayed on the Redskins' bench for the remainder of the first half.

Earlier Sunday, news broke that Philadelphia running back Brian Westbrook would likely miss his second straight game with post-concussion symptoms. Westbrook suffered a Grade 3 concussion in a Week 7 Monday night win at Washington.

Washington quarterback Jason Campbell also had to leave Sunday's game late in the first half with a chest contusion -- an injury that occurred on Atlanta's fifth sack of the game. Todd Collins replaced him for one play, but Campbell returned after halftime. Collins subbed in for Campbell again in the second half after Campbell appeared to roll his ankle.