It almost seems as if such injured Washington Redskins as running back Joe Washington, safety Mark Murphy and defensive linemen Bob Slater and Todd Liebenstein have disappeared into the creases of the team's five consecutive victories.

They are perhaps the most valuable of nine Redskins who, since the season began, have been placed on the injured reserve list for a minimum of four weeks. Now, they quietly rehabilitate while replacements such as Curtis Jordan (Murphy), Charles Mann (Liebenstein) and Keith Griffin (Washington) fill their spots with some vintage production.

Yesterday, Washington (strained knee) was back running lightly and humming loudly at Redskin Park. Liebenstein, still bothered by a rare bacterial infection, was saying, "When I get up in the morning sometimes, I feel like I'm 80 or 90 years old and looking for my cane." And wide receiver Alvin Garrett (on reserve with a severely sprained ankle) was saying, "I just got my cast off a couple days ago and I'm still walking around like I'm Fred Sanford."

Under this surface of silliness, though, a serious subplot to the 5-2 Redskins' season has been brewing:

Having already activated safety Ken Coffey and tight end Clint Didier, they can activate only three more players from injured reserve during the regular season. League rules limit them to five in all, plus a sixth in the postseason.

Furthermore, the players who have replaced these injured Redskins have, for the most part, performed well. For instance, look how well recently acquired wide receiver Calvin Muhammad (five catches for 104 yards last week) has performed in Garrett's spot, while even wearing Garrett's jersey number, 89.

So, two questions immediately arise: which three players will the Redskins reactivate, and what will happen to those players now starting in their absence? Remember, these are the very players who have had a big part in building that five-game victory streak.

"You have to evaluate how everybody is playing. We're not going to cross bridges before we come to them," Coach Joe Gibbs said yesterday. "But I have got to be truthful: When things are going well I'm reluctant to change."

Both Slater and Murphy are expected to start practicing next week, although neither is expected to be reactivated right away. Gibbs said Washington is "still a couple of weeks away. And once he's back, it will take seven to 10 more days of practice before he'll be ready to go."

The return of Washington, 31, is considered the most vital because of his pass-catching ability. Although Griffin has run for 142 yards, he hasn't caught a pass yet. Also, Washington would be the best replacment for John Riggins should the fullback's lower back pains ever force him to miss a game.

"Shoot, I can't ever tell when I'll be back. Once I thought I'd be out two weeks with an ankle injury and I was back the next day," said Washington, who hurt his knee in the 26-10 victory over New England four games ago and, like Murphy, is eligible to return for the Oct. 28 game against the New York Giants. "(Rehabilitation) is going real well. I've been running the last couple of days. I've been practicing coming out of my stance and all."

Murphy injured his knee in the second game of the season, a 37-31 loss in San Francisco. He missed two games before the team discovered his injury to be more serious than first thought. Murphy then was placed on injured reserve.

"Up until about a week ago, it hurt me to get out of a car," said the all-pro, who had missed only one game in his previous seven seasons and who was the team's leading tackler, with 26, after two games. "I can run on it better now. The only thing that hurts is when I cut on it. It's really hard to tell when I'll be back."

Asked if he thinks that Jordan might retain the starting spot, even if he is reactivated, Murphy said, "I really can't even think about that. It would be stupid for me to conjecture. I've just got to get healthy again."

Slater, the team's top draft pick from Oklahoma, and Liebenstein are eligible to be activated now.

Slater injured his knee in the final preseason game, at New Orleans, and reinjured it several weeks ago in his first day of returning to full-speed practice. Trainer Bubba Tyer said yesterday, "Bob's leg is back to 100 percent strength." Slater said, "I just hope things work out better when I try to come back this time than they did last time."

Liebenstein, a starter last year, said he might try to start practicing next week, although his status remains the most uncertain of the injured players. "I went out and tried running yesterday and it didn't feel that good," he said. "It's frustrating because this isn't really an injury where you can see progress."

Garrett likely won't return to practice for another three weeks. With only three roster reactivations available, players such as Garrett, linebacker Stuart Anderson, tackles Morris Towns and Curt Singer, a rookie, and tight end Mike Williams likely won't return this season, unless the Redskins risk exposing them to waivers first.

General Manager Bobby Beathard, realizing that each reactivation means one player must be cut from the active roster and that a controversy over who will be the starter at a certain position might arise, said, "Here's the way I look at it: With the bad luck that we've had with injuries this year, I think we will probably end up using all three of our (remaining) moves. Which way we'll go with the moves, I don't know. We'll have to wait and see how things work out."

St. Louis quarterback Neil Lomax fell on his right (throwing) elbow during practice Thursday and had fluid drained from the elbow, the team reported. Lomax is listed as "probable" (75 percent chance of playing) on the Cardinals' updated injury report.