Ken Houston displayed a full bag of tricks tonight. The big Washington winger posted the fifth three-goal game of his NHL career, with two of the three entering the net in weird fashion. He also engaged New York Islanders goalie Roland Melanson in a pair of slashing duels that saw both assessed coincidental minor penalties.

No other Capital caused Melanson any problems, however, and the Islanders had a hat trick man of their own, Bryan Trottier completing his into an empty net with 10 seconds remaining as New York won, 6-3.

It was the Islanders' seventh straight victory and extended some forgettable streaks against Washington. The Capitals are winless in 13 meetings against the Islanders since March 1980 and never have won a game in 19 tries at Nassau Coliseum.

The Islanders made maximum use of six shots to take a 3-0 lead in the first period. Each of Houston's goals then brought the Capitals within two, but New York was able to respond on each occasion, while Washington was failing to convert some excellent opportunities.

"The first period we were almost in awe of them," said Washington Coach Bryan Murray. "The last two periods we showed some desire, but they're a tough club when they get a lead."

Trottier scored twice on power plays in the first period. Both were set up by speedy Bob Bourne, who opened the scoring on the game's first shot after 36 seconds. On Trottier's second goal, Bourne raced down ice to beat the Capitals to the puck and avert an icing call.

Houston, meanwhile, was earning no extra credit, as he failed to get his stick on a Dennis Maruk pass that would have climaxed a three-on-one break.

In the second period, Houston became a factor. He brought the Capitals within 3-1 by poking the puck six inches on a play that began with Rod Langway shooting wide from the left point. The puck hit the rear boards and flipped crazily over Melanson into the crease, with Houston tapping it in as it rolled along the goal line.

"A couple of their guys and one of ours (Maruk) were whacking at the puck while it slid along and I was able to skate in and shove it across," Houston said.

Twice in the period Houston and Melanson drew coincidental minors for exchanging slashes while Houston tried to jam the slot on Washington power plays.

"In the power play, that's my designated position, a position I've been in for a lot of years," said Houston, his forehead bruised and cut from a similar encounter against Buffalo Saturday. "I didn't think I was intruding on Melanson's territory, but he thought I was, so things got a little bit heated."

On a power play early in the third period, Houston cut in from the left wing circle, eluded defenseman Denis Potvin and shot from close range as Melanson came out. The puck banged off the goalie's pad and again flipped over his head, this time landing in the net.

"I was standing there ready to hit it again, but I could see it was going in, so I didn't bother," Houston said. "I got a couple of lucky breaks in front of the net, but I missed a couple of other chances early in the game that might have turned it around a bit."

With 4 1/2 minutes left, Ken Morrow's 50-footer skidded past Washington goalie Pat Riggin to make it 5-2, Riggin being obstructed by Bob Nystrom as he tried to dive out and clear the puck.

Houston struck again 64 seconds later, on a rebound of a shot by Maruk. It was another power play goal, giving Washington two in seven chances, compared to New York's two for three.

"The difference in the game was their power play, their polish around the net, and all the chances we didn't take advantage of in two-on-one, three-on-two and three-on-one situations," Murray said.

"It's nice to score, but it's nicer to win," said Houston, as the Capitals fell to 2-4-1