As expected, Clinton Portis sat out practice on Wednesday and his status for the remainder of the week remains uncertain.

Portis has a sprained knee and he is questionable for Sunday's game against the Dallas Cowboys, according to head coach Jim Zorn.

"Clinton actually felt better [on Wednesday]," Zorn said. "Hopefully he'll continue to work in the athletic trainer's room and we'll see how it goes. I know he's going to be a game time decision. That's pretty much a lock there."

Portis sustained the injury in the Nov. 3 game against the Pittsburgh Steelers. His knee worsened during the bye week.

On Wednesday, Portis was able to fully straighten out the leg, providing Zorn with some optimism.

The team is in the process of fitting Portis for a brace, Zorn said, but it's uncertain if he would wear it.

"He wants to be back and he is working hard to be back," Zorn said.

Portis is second in the NFL in rushing yards with 995 and has seven touchdowns. He also has caught 18 passes for 150 yards.

If Portis is sidelined for the Cowboys game, then coaches could turn to a "community position" in which several running backs get carries.

Complicating matters is the status of Ladell Betts, who has missed the last three games with a sprained knee of his own.

Betts, who has 38 carries for 156 yards this season, participated in Wednesday's practice on a limited basis.

"Ladell made some cuts going to his left, and the injury is in his left knee," Zorn said. "I was impressed. The burst isn't there yet, but just the fact that he was in there pushing off and making cuts--that was encouraging how he continues to improve."

Said Betts: "I'm pretty much 50-50. It doesn't feel quite 100 percent, but we'll see how it progresses through the week."

If Betts is able to play on Sunday, then he would draw the start, Zorn said.

"We'd like to have Ladell in there as well, because that would kind of round out that position for us," Zorn said. "But if neither Portis nor Betts can go, then Shaun Alexander is going to have to come to play, and Rock Cartwright, too."

Alexander has had limited carries since joining the Redskins on Oct. 14. In three games, he has recorded 10 carries for 23 yards.

-- MOSS PRACTICES

Santana Moss was full-go in practice on Wednesday, a positive sign that he should be available for Sunday's game against Dallas.

"He was running hard and was involved in the game plan," Jim Zorn said. "He did very well. I was impressed."

Against Dallas, Moss has had some of the best games of his 8-year NFL career. In Week 4 earlier this season, Moss caught eight passes for 145 yards in the Redskins' 26-24 win over the Cowboys.

Overall, Moss has caught 41 passes for 747 yards--an 18.2 yards-per-catch clip--and four touchdowns in seven games against the Cowboys.

"I have had some great games against the Cowboys, but that's all it is," Moss said. "I'm never going to be too high on one team or too low on another. This is a big game.

"The Cowboys are a team where you want to bring something extra, because you know what they bring to the table. If you play well against the Cowboys, then that sends a statement like, 'This is what we can do to any team.'

"They're a good team, so you want to play well against them."

-- TAYLOR AND THOMAS

Jason Taylor batted down a pass during Wednesday's practice, and started to whoop it up with his teammates. That's a sure sign he is ready to return to action after sitting out the Nov. 3 game against Pittsburgh due to a calf injury.

"He looks like he is revving it up and he is participating at full speed," Jim Zorn said. "He is not just getting the reps, he is really working at it."

For Taylor, the game against Dallas promises to be a reunion with former Miami Dolphins teammate Zach Thomas.

Taylor married Thomas's sister, so the two have a close friendship that extends to family, too.

They both wear jersey No. 55 for their respective teams.

"It'll be different, for sure, to see him over there with another uniform on," Taylor said. "We're rivals now and we understand there is a lot riding on this game. The focus is on winning the game, and not rekindling any old friendship."

-- SPRINGS' STATUS

Shawn Springs is expected to return to practice on Thursday as he continues his return from a calf injury that has cost him four games this season.

"He was running [on Wednesday morning], so I think he is feeling better and better," Jim Zorn said. "I expect him to out there and, if not, surely by Friday.

"I imagine he will be active and participate in the game [against Dallas]."

With DeAngelo Hall added to the mix at cornerback, Springs could be called into action at safety. It's something that coaches continue to discuss.

"Every team wants to have their best players on the football field," secondary-cornerbacks coach Jerry Gray said. "If that means putting Shawn at free [safety] and letting LaRon play strong, and if that's going to be the best matchup for us, then that's what we do.

"But we haven't crossed that bridge yet, because Shawn hasn't played yet."