Joe Washington, the Redskins' most productive running back last season, will undergo arthroscopic surgery today to repair a cartilage tear in his left knee. Depending on the damage discovered during the operation, he could be out from three to six weeks.

The surgery, which will be performed by Dr. Stanford Lavine at Sibley Memorial Hospital, was scheduled after Washington's knee was given an arthrogram examination yesterday.

Washington hurt the knee making a cut in the first quarter of the Redskins' exhibition loss to Buffalo last Friday. Lavine waited until yesterday to make a final diagnosis, on the chance the knee would improve dramatically over the weekend.

"If we are lucky and the damage isn't too bad, he'll be out three to four weeks," Redskins Coach Joe Gibbs said. "If it's bad, it could be six weeks."

At the minimum, Washington will miss the first two games of the regular season, on the road at Philadelphia Sept. 12 and Tampa Bay Sept. 19. He could be absent from five or more games if the tear is major.

Gibbs indicated John Riggins and Wilbur Jackson would share Washington's running duties in the Redskins' one-back offense. Clarence Harmon and Nick Giaquinto, who is still recovering from an ankle sprain, will assume his receiving responsibilities on passing downs, although Jackson once caught 53 passes in a season. The Redskins were 0-5 last year in games Washington missed.

In another matter, the team cut five players yesterday to get within five of the 60-man roster limit that must be reached by 4 p.m. today. There was no decision whether Brad Dusek has retained his starting job at right linebacker or about his future with the team. Larry Peccatiello, the linebacker coach, said, "We are still in the process of evaluating everything. There may not be a decision until next week."

But the delay certainly doesn't seem to be a plus for Dusek, a team leader who is being challenged by Rich Milot and Mel Kaufman. If the Redskins were satisfied with Dusek's performance, there would be no need for an extensive discussion period.

Likewise, the future of receiver Terry Metcalf remains uncertain.

Metcalf, who suffered a serious concussion during the offseason, met with Gibbs late yesterday to discuss his future and emerged from the meeting "happier than I've been in months."

"I'm going to go for it in practice Tuesday," said Metcalf, who has not participated in any contact work since training camp opened. "Coach Gibbs and I had a good talk and I think he now knows I want to play.

"It's been very frustrating not being able to play. I think it's great they're worried about my health, but I told them not to worry any more."

Gibbs said before the meeting he still was weighing the options about Metcalf. The Redskins could try him in the final exhibition game at Cincinnati this Friday. If they think it is too risky (he has had two concussions in the last three years), they could waive or retire him. Some of Metcalf's friends, worried about his health, have urged him to retire.

The Redskins also have decided to let rookie Dan Miller do all place-kicking against Cincinnati. Miller is challenging Mark Moseley for the starting job, although the team is leaning more every day toward keeping both on the 49-man roster, barring a trade. League sources said yesterday there has been trade talk involving the Redskins' kickers.

"We feel like we really haven't had a chance to see him kick that much in a game," said Wayne Sevier, the special teams coach, of Miller. "We'll give him the whole game and see if he can handle it. If he does, we have a bigger dilemma. If he doesn't, it might help us make a decision. We already know what Mark can do."

Washington's injury is a major setback to the Redskins, who are 0-3 in exhibition games. He was their most valuable player last season, running for 916 yards and catching 70 passes. Just as important, he gives the team quickness that can't be replaced by any of his teammates.

"He means so much to our offense, but we just will have to pick up the slack," quarterback Joe Theismann said. "Without him, it's up to us to get sharper on offense and execute better than we have. I just hope he can come back as soon as possible."

Don Breaux, the running back coach, said that with Washington out, the key player now is Jackson. He is quicker than Riggins and played well last year as a solo back before hurting a knee.

"Wilbur Jackson has got to protect the ball for us," Breaux said. "He can give us what we need from a running standpoint. No one has Joe's quickness, but Wilbur has proven he can do it. We've talked to him about his fumbling and we'll continue to talk. He has to be aware of it and stop it."

Jackson, who fumbled twice against Tampa Bay on Aug. 21, said he is aware of the team's unhappiness, "but I told Coach Gibbs I'd concentrate more and do everything I can to not fumble.

"It's something I don't want to do. I'd like to forget about it, but it's always in front of me. It keeps getting brought up; they keep saying, 'Clutch the ball, tuck it in.' I never thought it was a problem but evidently it is and I have to improve."

Riggins has had an outstanding training camp and exhibition season, but the Redskins would prefer not to overwork him. His presence alters what running plays the team can use and the style (more power and less quickness) Gibbs can feature.

"Fortunately for us, running back is one of our deepest positions," Gibbs said. "We just have to go without Joe and have the other guys fill in. They'll have to carry us."

The Redskins' five cuts yesterday were: guards Juan Taylor and Gary Sayre, center Lee North, quarterback Chris Garrity and defensive tackle Pat Ogrin. Earlier, they had released defensive back Willie Holly and signed safety Tom Deery ...Center Jeff Bostic has a hyperextended elbow but Gibbs expects him to play Friday . . . Defensive end Dexter Manley is still bothered by a hip pointer.