Canadian pride rests in the Vancouver Canucks tonight as they open a seven-game series trying to prevent the New York Islanders from becoming the first United States-based team to win the Stanley Cup three years in a row. Faceoff is 8 o'clock at Uniondale, N.Y.

Only the Montreal Victorias, Ottawa Silver Seven, Toronto Maple Leafs and Montreal Canadiens have retained hockey's biggest prize for three straight seasons since Frederick Arthur, Lord Stanley of Preston, placed it in competition in 1893.

Never before have two teams from the opposite coasts of North America met in a final series, so this one promises to set records for travel, if nothing else. Game 2 is scheduled in Uniondale Tuesday night, with Games 3 and 4 at Vancouver Thursday and next Saturday nights. The if-necessary games are scheduled for May 18 at Uniondale, May 20 at Vancouver and May 22 at Uniondale.

Many critics of the current playoff process foresee little of merit in a final matching the National Hockey League's finest team and a Vancouver club that finished the regular season 30-33-17. Only two teams, the 1949 Maple Leafs and the 1938 Chicago Black Hawks, have captured the Cup following sub-.500 regular seasons.

The principal requirement for success by an underdog, however, is outstanding goaltending, which the Canucks have right now in Richard Brodeur, a 5-foot-7, 160-pounder who spent a lifetime with the Islanders one season.

Brodeur has played all 13 playoff games for the Canucks, winning the required 11, and has a goals-against average of 2.32. He has blocked 431 of 463 shots for an impressive 93.1 percent save ratio.

"I couldn't believe we'd be here two months ago," Brodeur said after the Canucks eliminated the Black Hawks in Chicago, 6-2, on Thursday. "The Islanders have to be the best team in the league right now, but we're going pretty good, too, and I think we can do it."

Brodeur was drafted by the Islanders in 1972, but joined Quebec of the World Hockey Association instead. Claimed by the Islanders as part of the 1979 merger, he played only two games as third man behind Chico Resch and Bill Smith. He went to Vancouver a year later for no more than a flip flop of No. 5 draft picks.

"If we continue to get the goalkeeping we have, and we work this hard, no matter who we're playing I think we can win," Vancouver Coach Roger Neilson said.

It had been determined earlier this season that Neilson, the assistant to Coach Harry Neale, would become head coach next year, with Neale moving up to general manager and Jake Milford, the current general manager, becoming team president. So, when Neale was assessed a 10-game suspension for fighting with fans in Quebec, it was natural for Neilson to take command.

What followed was unnatural. The Canucks went unbeaten through their last five regular-season games, swept Calgary in a three-game preliminary playoff and split the first two games of the Smythe Division final against Los Angeles. Although Neale was eligible to return at that point, he decided to leave Neilson in command.

The Canucks won the next three from the Kings, then beat Chicago for the Campbell Conference title, 4-1. That adds up to a 15-2-1 record for Neilson, who felt compelled to point out that none of those 18 games was against the Islanders--or anyone else with a winning record.

"It's a bit of a surprise for us to get this far so easily, but keep in mind that all the teams we've beaten finished below us in the standings," Neilson said. "I do think, though, that L.A. and Chicago, as well as our club, were playing better than the standings indicated."

The Canucks beat the Islanders in Vancouver, 4-3, during the regular season and dropped a pair of 4-1 decisions at Nassau Coliseum. The teams last met on Jan. 4, however, which makes the results largely irrelevant.

"The key to beating the Islanders is shutting down (Mike) Bossy and (Bryan) Trottier," Neilson said. "We have to keep finishing our checks and try to outwork them. It's going to be a mammoth job.

"Having to play so soon after Chicago is tough. If everybody was healthy it wouldn't be too bad, but we've got a lot of bruises. If we could have waited until Tuesday, it would have been a lot better."

Neale, the man of many quips, put the upcoming quest in perspective: "We should have a handicap. If the Islanders don't wrap it up in five games, they should let us take the Cup home."