Washington Capitals defenseman Larry Murphy has suffered a fracture of the navicular bone in the left foot, which is expected to keep him out of action for three weeks. Initial X-rays taken after Tuesday night's victory over St. Louis had proved negative.

Combined with Rod Langway's continued absence with a strained ligament in the right knee, Murphy's misfortune puts pressure on the Capitals' defense, with a home-and-home series against the rival New York Islanders Friday and Saturday.

Down to five defensemen, the Capitals do not have a healthy backliner in their minor league system, either. However, Yves Beaudoin was due to return from a minor knee injury last night in Binghamton and he was told, if he encountered no problems, to come to Washington this morning, prepared to make his NHL debut on Friday.

"As long as Yves Beaudoin is in shape, he's coming up," said General Manager David Poile. "I made a few calls today to see what is available, but this is a poor position to be in trying to make a deal. To get short-term help, we'd have to pay an excessive price.

"It will probably be two to three weeks before we have both of them back. I don't want to make a long-term sacrifice for a short-term problem, so some of the players we're dressing will have to put in some extra ice time. Of course, if we have any further injury problems, we'll have to consider something else, like signing and calling up one of our junior draftees."

The only other defenders assigned to Binghamton by the Capitals are injured, Timo Blomqvist with a groin pull and Grant Jennings with stretched knee ligaments. Marc Chorney retired rather than continue in the minors.

Murphy was hurt when he blocked a shot with the unprotected side of his skate during the second period of Tuesday's 6-3 victory over St. Louis.

"One of their guys took a shot from the blueline and I stuck my foot out to stop the puck," said Murphy, who plans to swim to stay in shape while waiting for the bone to heal. "It stung, but I didn't think about it. I skated four or five more shifts before I realized something was wrong and I had to leave."

Murphy had three assists in little more than half the game and nine points in the Capitals' first 10 games.

Since Langway was hurt a week ago, Coach Bryan Murray had rotated five defensemen -- Murphy, Scott Stevens, Peter Andersson, Darren Veitch and Kevin Hatcher -- and used Dwight Schofield on occasion. Now Schofield will be given extra ice time, something he undoubtedly deserves considering his status as the team's plus-minus leader at plus four.

"I'm glad just to be dressing for every game," said Schofield, claimed from St. Louis in the waiver draft Oct. 7. "That plus three (Tuesday) was nice to get against my old team, even if all I had to do was go out and watch Garts (Mike Gartner) score goals. This weekend will tell. The Islanders are a tough club."

If an emergency arises against the Islanders, Murray always can call on Dave Christian, who moved to the backline with the U.S. Olympic team two months before the 1984 tournament at Lake Placid and did a superb job on defense in the gold-medal push. "I don't mind it there," Christian said after practicing the backpedal during yesterday's workout at Mount Vernon. "It's one of those things. If they feel they want me to play back there, I feel I can play there."

Murray indicated that such a shift would be a last resort, not because he lacked confidence in Christian as a defender but because he preferred to have him skating at center.

"David has played defense and that's definitely a possibility," Murray said. "But he's not the type of guy we want to move back. We need him up front.

"One way we can help the guys who will be doing the work back there is to move Mike Gartner to the point on power plays. And we've been doing some new things in the offensive end, but now we'll have to play more disciplined and have the third man be more responsible. With that kind of help, the guys we have can do the job back there all right.

"It's a tough way to go into a big weekend, but there's also a positive aspect to the situation. Having the injuries now allows other people to get extra ice time and work on penalty killing and the power play. In the long run it will help them and us, as long as the injuries end in three weeks and we don't get any more bad ones."