BOSTON — With five minutes left and his New York Islanders bleeding away their three-goal lead, coach Barry Trotz called a timeout and told his players to breathe.

“He just calmed everyone down,” said forward Josh Bailey, who had a goal and an assist in the 5-4 victory that gave New York a 3-2 lead in the second-round series. “He told us to apply pressure, not sit back. Just getting everyone focused. You need that at certain times, and I thought that was a good time.”

Mathew Barzal scored one power-play goal and assisted on another, and Semyon Varlamov stopped 40 shots Monday night, when the Islanders opened a 5-2 lead and held on to move within one win of the Stanley Cup semifinals.

New York would reach the NHL’s final four for the second straight season with a victory in Game 6 at home on Wednesday.

“We’re excited to go back to the Coliseum,” forward Jordan Eberle said. “You’ve seen how loud it is. It gives us some juice.”

Barzal scored for the third straight game, and Kyle Palmieri, Bailey and Eberle all had goals in the second period, when the Islanders opened a 4-2 lead. Brock Nelson made it 5-2 just two minutes into the third, after Jeremy Swayman replaced Tuukka Rask in Boston’s goal.

But David Pastrnak scored his second of the game two minutes later, and David Krejci brought Boston within one goal with 5:19 left in the third period.

That’s when Trotz used his timeout.

The Bruins pulled Swayman in the final two minutes for an extra skater, but didn’t really threaten before the Boston fans pelted the ice with cups and giveaway towels after what could be the final horn of the season.

“We’re going to New York to win a game, and that’s all that’s on our mind,” Boston defenseman Charlie McAvoy said. “We want to put our best foot forward and win a hockey game — that’s it. That’s all we’re thinking about right now. This thing isn’t over.”

The Islanders were successful on three of four power plays while getting called for just two penalties all game.

Bruins coach Bruce Cassidy didn’t like that.

“I think they sell a narrative over there that it’s more like the New York Saints, not the New York Islanders,” he said.