With the NHL playoffs fast approaching, two teams have decided to make changes -- starting at the top.

Gerry McNamara was fired yesterday as general manager of the Toronto Maple Leafs, the team announced, while Larry Pleau, coach of the AHL's Binghamton Whalers, was named to replace Jack Evans as coach of the Hartford Whalers. Emile Francis, team president and general manager, made that announcement yesterday in Hartford.

Pleau was to take over immediately, for last night's game, ironically, against Toronto, Francis said at a hastily called news conference.

The announcement came after the Whalers lost four in a row and following a report Friday that Evans was contemplating retirement.

Bob Stellick, Maple Leafs publicist, said owner Harold Ballard gave McNamara "the opportunity to resign but he chose to be fired. Mr. Ballard will name a replacement in the near future."

Stellick refuted rumors that surfaced Sunday that McNamara would be replaced by one of two Toronto scouts, former player and coach Floyd Smith or former player Dick Duff. Stellick did not say if McNamara had been offered another position with the team.

McNamara's job and that of Coach John Brophy had been in jeopardy because of the Maple Leafs' long losing streak. The team has only one victory in its last 21 games, dating back to Dec. 23.

Ballard, who returned home Saturday from Florida where he spent almost a month in a Miami hospital after suffering a heart attack, had said that McNamara, not Brophy, would be the one to go if the beleaguered Toronto general manager couldn't offer a good enough reason for the Maple Leafs' poor performance since Christmas.

The Maple Leafs went a record 15 straight games without a victory in that stretch.

Hartford's Evans had been quoted in published reports as saying that he would continue coaching through the term of his contract, but that he would retire after the end of next season.

Francis said the comment surprised him and he immediately decided on a coaching change.

"I want to make it perfectly clear that the coaching change had nothing to do with the coaching performance of Jack Evans," Francis said. "I respect his decision on retiring . . . but his comments were ill-timed and I feel it would not be in the best interest of our hockey club to have him continue as head coach."

Francis said Evans would continue working for the Whalers, first as a scout at the Winter Olympics in Calgary and later at other assignments. His contract runs through the end of the 1988-89 season.

Pleau, 40, will be under contract through the 1989-90 season.

"I look forward to the challenge," Pleau said. "I have always looked forward to returning to the NHL as a coach and feel this is an extra special opportunity."

Pleau was the first player signed by the New England Whalers when they were a charter team in the old World Hockey Association.

Since the 1983-84 season, Evans had coached the Whalers for a team-record 374 games, compiling a 163-174-37 record. This season, the team was 22-25-7 and in fourth place in the Adams Division.

Last season, Evans coached the Whalers to a club record 43 wins , winning the division title.

Whalers 4, Maple Leafs 2:

In Hartford, centers Ron Francis and Carey Wilson scored two goals each and Sylvain Turgeon added three assists to make Larry Pleau's return as coach of the Whalers a success.

Rangers 6, Penguins 3:

Marcel Dionne scored his 717th career goal, tying him for second place on the all-time list with his boss, General Manager Phil Esposito. Dionne's goal came during a four-goal first period in New York.

Bruins 6, Devils 3:

Reed Larson scored on a 90-foot slap shot in a four-goal first period in Boston as the hosts regained the Adams Division lead.

Blackhawks 5, Nordiques 5:

Bob Murray scored his fourth goal of the season with 2:12 remaining in regulation to tie host Quebec.

Flames 5, Kings 2:

Joe Mullen scored his 28th and 29th goals this season and rookie Joe Nieuwendyk set a club scoring record with his 40th goal as Calgary broke a three-game losing streak with a victory in Inglewood, Calif..