Clinton Portis suffered a concussion and Jason Campbell suffered a high ankle sprain in Sunday's 31-17 loss to the Atlanta Falcons.
Portis did not return to the game, but Campbell was able to come back to lead the Redskins' offense.
Portis was knocked out on a run play late in the first quarter, according to head coach Jim Zorn.
His status for practice this week and next Sunday's game against the Denver Broncos is uncertain.
"We're going to be cautious with it," Jim Zorn said.
If recent past is any indication, he could miss at least one game.
On Oct. 26 at FedExField, Philadelphia Eagles running back Brian Westbrook suffered a concussion after he was tackled by London Fletcher. Westbrook, who was also reportedly knocked out on the play, missed one game but was expected to return to action this week.
Portis was on the sidelines in the second half watching the game in street clothes.
He finished the game with four carries for four yards.
He suffered the injury on a 9-yard run in which he was tackled by cornerback Chevis Jackson and safety Thomas DeCoud. The play was nullified due to a holding penalty on Casey Rabach.
Portis watched the rest of the game from the Redskins' sidelines.
Campbell suffered his ankle sprain midway through the fourth quarter as he was trying to lead a Redskins comeback.
He sat out the rest of the series, but was back on the field for the Redskins' final drive.
Campbell also was injured in the first half after he was sacked by defensive tackle Jonathan Babineaux and defensive end John Abraham. Campbell missed a play late in the first half after suffering a chest contusion.
Both times, Campbell was replaced in the lineup by Todd Collins.
Campbell finished the game with 15-of-24 pass completions for 196 yards, one touchdown and one interception. Collins was 4-of-5 for 12 yards.
Mike Williams suffered a sprained ankle in the fourth quarter as well. He was seen walking in a protective boot as the team departed Atlanta.
Williams was replaced by D'Anthony Batiste.
Also, Reed Doughty suffered a sprained knee in the fourth quarter and did not return to the game.
"We've got to get a diagnosis on that," Zorn said.
