Boston’s David Pastrnak, left, collides with Montreal’s David Savard during Thursday’s game in Boston. Steven Senne/Associated Press

BOSTON — David Pastrnak scored his 49th goal, Tyler Bertuzzi had a goal and an assist and the Boston Bruins overcame a sluggish performance to beat the Montreal Canadiens 4-2 on Thursday night for their fifth straight victory.

Jake DeBrusk scored on a breakaway, David Krejci put home on a rebound midway through the third period and Jeremy Swayman stopped 29 shots for the Bruins, who managed 21 shots and went 0 for 5 on the power play.

Boston’s Jake DeBrusk, left, celebrates with defenseman Connor Clifton after DeBrusk scored in the first period against Montreal on Thursday in Boston. Steven Senne/Associated Press

While they were denied a chance to clinch the Atlantic Division when Toronto beat Florida, the Bruins improved to 55-11-5 and remained on pace to break the league record of 62 wins in a season.

Nick Suzuki and Kirby Dach each scored power-play goals against Boston’s No. 1 penalty kill, Suzuki added an assist and Jake Allen made 17 saves in Montreal’s 10th loss in 12 games.

The 932nd meeting between the Original Six rivals and their only matchup in Boston this season was chippy. There were 31 penalty minutes in the first period, including a game misconduct against the Bruins’ A.J. Greer after his crosscheck to the face of Mike Hoffman as they awaited a face-off.

The Canadiens got within 2-1 on the ensuing power play on Suzuki’s one-timer with 19 seconds left. It was the first goal allowed by Swayman after consecutive shutouts.

But Swayman made two tremendous saves to start the second period before Pastrnak buried a shot from the low slot to give him a career season-high in goals. Allen later robbed Pastrnak in his bid to get No. 50.

Krejci’s backhander at 12:16 gave Boston a cushion. Pastrnak earned the secondary assist to give him 95 points.

Boston took the lead just 4:34 in when Bertuzzi picked up his first goal since being acquired from Detroit on March 2. And it was an odd one. His feed from behind the net bounced off Canadiens defenseman Mike Matheson’s stick, then banked in off the back of Allen’s leg.

DeBrusk raced past a colliding Joel Edmundson and David Savard and scored seconds after a Montreal power play expired to make it 2-0 at 13:38.

But the Canadiens, last in the Atlantic and eyeing the draft lottery, rallied despite more injury issues. While Montreal welcomed back Jake Evans (knee) after a 28-game absence, it played without Josh Anderson, who appeared to injure his right ankle in the final minute of Tuesday’s 3-2 win over Tampa Bay.

Evans missed the net while skating in alone looking for the tying goal early in the final period.

NOTES: Boston’s Brad Marchand, known for hot takes and dust-ups on Twitter, said he deactivated his account after being told his verified blue check mark would be taken away unless he paid a monthly fee. “So I said, ’You know what? I’m going to get out now while I can,’” Marchand said, adding, “I’ve got enough expenses.” … Evans, injured on a draw in the final seconds of the first period on Jan. 14 when New York Islanders center Brock Nelson fell on his left leg, was happy to avoid surgery. “Obviously a much larger man fell on my knee,” Evans said. “I was pretty worried for a second. It felt like my knee kind of separated from my body.” … Boston’s Taylor Hall (lower body) has begun skating, but Coach Jim Montgomery isn’t sure if he’ll return before the playoffs.