Back in the 1950s, the Montreal Canadiens' power play, featuring Boom Boom Geoffrion, Rocket Richard and Doug Harvey, was no potent that it forced the National Hockey League to change the rules. Instead of a penalized player serving the two minutes of a minor penalty, he was released early when the team with the manpower advantage scored.

That rule is still in the books, so there is no way to legislate against the domination of the New York Islanders' power play. There seems to be no way to defend against it, either. The limit of Mike Bossy, Bryan Trottier, Bob Bourne, Denis Potvina and Mike McEwen is so potent that it is forcing opponents to sacrifice aggressiveness, out of fear of the consequences of a possible penalty.

The New York Rangers, who reached the semifinal round of the Stanley Cup through effective use of muscle, restrained themselves against the Islanders and were swept away in four games. The Minnesota North Stars, adhering to similar strategy, are halfway to the same fate in the final series, which resumes here Sunday night.

The Islanders had already established a playoff record of 26 powerplay goals, one more than the mark they set in winning the Cup last year, before this series began. Thursday nigth in Nassau Coliseum, they added two goals to it, in just two chances, as they earned a 6-3 victory.

With the game tied, 3-3, the North Stars' Neal Broten was sent off by referee Bryan Lewis for a marginal hooking violation on Clark Gillies. Potvin then scored his second goal of the game to put New York in front to stay.

It was Potvin's sixth power-play score of the playoffs. Bossy, who also had two goals, including a first-period extra-man score, has nine, another Stanley Cup record. The Islanders' power play has been successful an amazing 40.6 percent in the playoffs after leading the league with a 29.3 percent mark in the regular season.

The North Star complained bitterly about the call on Broten and felt that Lewis, the object of changed obscenities by New York fans, was looking for anything possible to try to reduce an imbalance that saw the Islanders receive 14 penalties to Minnesota's eight and kill two lengthy overlaps in which they were two men short.

"I told everybody on the bench not to touch anybody, because one was coming; and take a look at what came" said Minnesota Coach Glen Sonmor. "That call on Broten, after what had been going on without being called, was criminal. Unfortunately, there's a quota system on penalties in this league. We had to expect a penalty in return, and it happened."

What obviously frustrated Sonmor into making those remarks, which guarantee a fine from the league, was the way the North Stars had backed off, harnessed themselves, to try to keep the play at even strength.

Although Sonmor could truthfully say that, "We looked more like ourselves and we skated better," the North Stars were consistently outhit and pushed off the puck. The Islanders, confident in their ability to handle the North Stars' power play after those devastating shorthanded goals Tuesday, risked penalties to dominate the game physically -- and succeeded.

Bourne threw such a bruising chop on Minnesota defenseman Fred Barrett in the first period that Barrett lay on the ice for several seconds, rose to his feet and fell back. The Islanders have hit in that fashion throughout the first two games and it has been the major difference.

"We can come back," Sonmor said. "Home teams win a whole lot more games. In the playoffs, home ice is not as big a factor, but at least we'll have the crowd yelling for us and, I hate to say it about officials, but the crowd obviously does have an influence.

As if the North Stars were not frustrated enough on the ice, they found their Long Island visit a disaster in other ways. They had intended to come home today on a commercial flight, but switched to a postgame charter when they were advised the rooms at their Westbury, N.Y., motel had already been booked for Thursday night.

The bus carrying club officials and media personnel broke down at the Coliseum, so the players were forced to wait more than an hour at LaGuardia Airport. Then the equipment and luggage proved too heavy and some gear had to be left behind. Finally, there was a long wait for luggage at the airport here, so the players did not get home until after 5 a.m. CDT. a