BOSTON — The notion that the Islanders are always in every game, no matter how outplayed they are, was truly put to the test.

As the Bruins commanded every area of the ice for 60 minutes, the Islanders still found a way to pull out a 5-4 win in a swing Game 5 on Monday night at TD Garden. Persisting through spurts of relentless play from the Bruins before pouncing on mistakes has just been the Islanders’ M.O. this series, and it’s earned them a chance to clinch heading back to Nassau Coliseum for Game 6 on Wednesday night.

The Islanders were walloped every which way — along the boards, in the neutral zone and were hammered into their own end for a good portion of the game. Though, as they have many times before, the Isles bent but didn’t break and made it work.

“You know they’re gonna have a push,” said Josh Bailey, who potted the go-ahead goal at 14:30 of the second period to give the Islanders a 3-2 lead. “They’re a resilient group over there, they’re not going to quit. We just tried to stick to our game plan, it maybe got away from us at times, but guys just kept fighting. Guys are paying the price, blocking shots, doing everything they can to get the win.

“We’ve earned ourselves an opportunity here at home.”

Boston nearly got the Islanders to crack, when the Bruins turned a three-goal deficit into one with 5:17 left in regulation after pulling goalie Tuukka Rask in favor of rookie Jeremy Swayman to start the third. The Islanders struck first in the final frame, with Adam Pelech jumping to keep the puck in at the blue line, which led to Brock Nelson’s 5-2 score.

But Bruins top-line winger David Pastrnak buried his second goal of the night, which came on the power play, before David Krejci stuffed another one in to set the Bruins up to cause havoc in the final minutes.

Islanders head coach Barry Trotz called a timeout and sent his players back out on the ice to buckle down and fend off the Bruins’ inevitable late push.

“We were backing up, and I don’t like that, that’s not our style, you want to go forward.” Trotz said of his message in the timeout. “I said, ‘Let’s get back to our game, let’s get back to our game of pushing forward.’ I thought we stabilized.”

The power play has been a problem all season, but the Islanders made it their strong suit when they needed it most, going 3-for-4. Their three man-advantage tallies marked the first time they scored that many in a playoff game since the team scored four in Game 3 of the Eastern Conference quarterfinals against the Maple Leafs on April 23, 2002.

After Mathew Barzal’s power-play goal at the end of the first period evened the score 1-1, the Islanders earned another man-advantage opportunity less than three minutes into the middle frame. Bailey sent a saucer pass through Bruins defenseman Connor Clifton’s skates, to Kyle Palmieri at the far left post for the easy tap-in and the Isles’ first lead of the night.

Later in the second, Bruins fourth-line winger Chris Wagner was called for high-sticking and the Islanders went back to work. Taking a cross-ice pass from Barzal, Jordan Eberle picked the far corner to take a 4-2 lead at 16:38.

“We made some adjustments,” Trotz said of the power play. “Guys executed on those adjustments. That’s what playoff hockey is all about.”