We might have just been expecting to win instead of doing something to make it happen," said Denis Potvin, captain of the New York Islanders. "We've got to start making it happen."

The Islanders were defeated, 4-2, by the Washington Capitals Thursday night, and instead of a comfortable 2-0 edge in their preliminary-round playoff series, the Islanders will have to work themselves back to the top, playing a pair of games at Capital Centre today and Sunday night.

The series split erases the Islanders' home-ice edge and gives Washington the advantage.

"We've just got to play better tomorrow (Saturday)," said Islanders Coach Al Arbour before today's practice. "We just didn't do anything much. We didn't skate, didn't forecheck, we weren't working."

Arbour looked less than pleased with his club's performance, and added, "I don't know if we are taking things for granted, if that's got something to do with it, but we'll have to be better Saturday."

Potvin, whose third-period goal cut the Capitals' lead to 3-2 and seemed to ignite his team for a comeback, said he wasn't sure precisely what the Islanders' problem was. "Besides the shots just not going in, we didn't work as hard as we had the night before," he said. "We didn't play as well, and they played with much more intensity. We weren't forcing them into their zone enough either. I just don't think we played well."

Bob Nystrom, who scored the first New York goal Thursday night, said he felt the team could have turned around after Potvin's goal. "That was a big, big goal for us, the kind of thing you certainly can take advantage of. I felt we were right back in it then," he said. "They had to feel a little pressured then. And at that point, we should have been putting more of the pressure on ourselves."

He shook his head. "No way they should have won it, that's all."

Did he mean Washington had not played well enough to win? "Oh, no, not that, just, well they shouldn't have won . . . Now we'll have to go out and win two in their place."

Nystrom said the Islanders power play, which was zero for two, was "certainly a deflating factor. We had capitalized on our power play before, but it didn't work out that way in the second game."

Washington's use of three defensemen for a good part of the game, Nystrom said, "was a tribute to their people. That they've got such good ones, they can use three. We really had to work against it the whole night. And it worked for them."

Arbour would not indicate what changes he planned for the next two games, but said he definitely would not try to bring back Clark Gillies, who suffered a sprained left knee and missed the last three games of the season. He is out indefinitely, and Arbour said there was "no possibility, none whatever" of bringing him back during this series.

The Islanders, who skated through a brief, businesslike practice before leaving for Washington, had few smiles and fewer answers for their performance the previous night. When asked what he would do differently on Saturday, goaltender Billy Smith shrugged his shoulders slightly.

"Who knows?" he said. "Who knows?"