The Washington Capitals took a 5-0 lead over Edmonton in the first period yesterday and 15,889 Capital Centre fans sat back to enjoy a laughter. The folks could not suppress their giggles as the Oilers' Jari Kurri carried the puck into the side of his own net early in the second period.

By the five-minute mark of the third period, however, one and all were reminded that nothing ever comes easy for the Capitals. The Oilers crept within 6-4 and boos were heard.

Dennis Maruk's second goal of the game and 35th of the season, after a false alarm, finally eased the tension and the Capitals prevailed, 7-4, expanding their unbeaten streak to four games and climbing to both the 50-point plateau and 11th place in the NHL.

"We had a big lead and we got lazy," said Maruk, voted the No. 1 star for the fourth game. "It happens to every team. Sure, we were concerned when they got close, because they're an explosive team. They beat Montreal the other night, 9-1. But we came back and scored instead of them and we got two big points."

Lee Fogolin and Brett Callighen scored in the first 5 minutes 7 seconds of the third period as the Oilers swarmed all over Washington goalie Mike Palmateer. Then a hooking penalty to Edmonton's Stan Weir provided Washington's scorned power play with a chance to make an important contribution.

Some fancy passing from Jean Pronovost to Guy Charron to Maruk turned on the red light behind Edmonton goalie Pete LoPresti, but referee Denis Morel ruled that Maruk had kicked the puck into the net.

"I directed it," Maruk admitted. "The guy had my stick and there was nothing else I could do. You never know. Some refs call it, some don't."

Undaunted by the washout, Maruk intercepted a Wayne Gretzky pass at the Washington blueline and initiated a play that ended with Rick Smith dropping a pass to Maruk and providing the screen that enabled Maruk to beat LoPresti with the seventh goal.

It was the fifth straight game in which Maruk has scored a goal. He has seven over that stretch and four in the last two games. This was also the second straight game in which Washington's much-maligned power play produced two goals.

Washington has another two-goal scorer, a most unlikely one judging by rumors that had been spread via talk shows and printed word in the past month. That was Rolf Edberg, supposedly consigned to Swedish oblivion.

Edberg, who did not even travel to Pittsburgh for Saturday's 4-4 tie, phoned Coach Gary Green yesterday morning and said he was ready to play. Moreover, he wanted to play very badly. At game, Edberg was in the starting lineup with Bengt Gustafsson and Dennis Ververgaert, and that trio accounted for three-fifths of the first-period blitz.

Maruk scored first, after grabbing Mike Gartner's deflected shot from the point on a power play. It was proper retribution.Edmonton's Doug Hicks having gone to the box for knocking Maruk into the Oiler net.

Then the Swedes took over. First Edberg picked off a Paul Coffey pass in front of the Edmonton net and fired it past Eddie Mio before the Oiler goalie could move.

Defenseman Jim McTaggart, a solid performer in a five-defenseman setup that lacked Rich Green, knocked Roy Sommer off the puck at the Edmonton blueline and fed Gustafsson, whose 45-footer made it 3-0.

Ververgaert's long pass along the right-wing boards set up the fourth goal, with Gustafsson skating toward the net and making a perfect pass to Edberg after pulling the defense his way.

That made only six goals for Edberg, but he was most grateful to reach that figure. It has been a forgettable season in which Edberg has been frequently troubled by a ligament problem at the base of his spine.

"It has been a long, long season for me so far, but I am glad I have 30 games left to do something," Edberg said. "I should have had the third one tonight, but I am happy with two goals.

"It is the same with Guy (Charron) as with me. The pressure is on. I have to produce goals and work hard. If I don't score, maybe the next game I sit down. I don't know what is in the coach's mind. If I don't play much or in the right position, I get shaky. If I miss the first chance, I start to think, 'Don't miss the second.'

"My back, it feels really good now. I come back and play five games -- the first three are pretty good, then I don't have the legs and I have a bad throat and I have to sit out two games. Today I get a new chance."

Howard Walker fed Jean Pronovost for a breakaway and a 5-0 lead. Mio hardly moved on that one and Sather moved quickly to bring in LoPresti in relief. The rest of the way it was mostly Edmonton.

"When you completely dominate a team like that for a period, the odds are against you being able to keep it up," Gary Green said. "I told them to be careful, to try to stay sharp. Obviously, we played with the percentages, no question about it. "I don't like periods where you completely blow a team off the ice. A team tends to a psychological letdown, the players think about getting a lot of points and forget the hard work involved in getting them. I would like to try it again, though. I think I'd say something else at the end of the first period."

Aside from Maruk's finale, the only other Washington goal after the big first period was scored by Alan Hangsleben, his first since Oct. 24. Coming out of the penalty box with Washington ahead 5-1, he trailed Gartner down the ice, pounced on Gartner's deflected shot behind the net and came around to fire at LoPresti. The relief goalie blocked the shot, but Hangsleben persevered and scored on the rebound.

"I'm not supposed to score; I'm a defenseman," Hangsleben said.

In the third period, he was back on defense, lending a lift to the beleaguered backline corps. Rick Green suffered a severe groin pull Saturday and it is not known when he can return.

A last note: The only other time the Capitals scored five goals in the first period, on Nov. 14, 1978, they had to come from behind to beat Atlanta, 8-7.