The Bruins keep finding new, torturous ways to lose hockey games.

The B’s coughed up a pair of two-goal leads and then gave up a power-play goal with 1:10 left in regulation to lose to the Vegas Golden Knights, 4-3, at the Garden.

Pavel Zacha was called for slashing with 3:10 left in regulation and, when the B’s failed to clear on several chances, Pavel Dorofeyev pounced on a loose puck and lifted it over a sprawling Jeremy Swayman with 1:41 left in regulation. But Mark Stone was in the crease and made contact with Swayman and the B’s challenged for interference. It was a good challenge and the goal came off the board.

But the B’s could not make good on it. As Zacha’s penalty was up, Tomas Hertl scored from the slot to make it 4-3. That’s how it ended.

“We have to kill that off after (the goal was overturned),” said a frustrated coach Joe Sacco. “That’s a huge momentum boost for us right there on the disallowed the goal. We just have to do the job there and get the kill after that. We should have got it done and we didn’t.”

Vegas, which outshot the B’s 38-24, cashed in on two of their three power plays and a bad goal from Swayman late in the final minute of the second period to register the come-from-behind win. And so on a day that started so well ended with the B’s getting nothing in the standings.

Despite the painful loss, captain Brad Marchand continued to express belief in the team.

“I think we can play with anybody. The difference in the games are very small margins, small details,” said Marchand. “We just have to clean it up a little bit. But I think we can play with anybody.”

Time, however, is running out. There are 25 games left after the break and, on Saturday, the missed a chance to climb back into a playoff spot, even if it was only for fleeting moment.

The Bruins took a 2-1 lead into the first break after an eventful opening 20 minutes.

Marchand notched his 20th goal of the season at 3:17 and it was one of the easiest ones he’s scored in his career. Nikita Zadorov spotted an undefended Marchand at the side the net and he hit the captain with a perfect pass for the tap-in. The tally marked the 14th time in his career that Marchand reached the 20-goal plateau.

The B’s had several excellent scoring chances. Morgan Geekie had a glittering chance on a 2-on-1 when David Pastrnak delivered a beautiful pass. With a ton of room upstairs, Geekie was robbed by Ilya Samsonov with a sprawling glove save.

The B’s did take a 2-0 lead at 13:49. The Marchand line stormed the Vegas net and Samsonov made at least one excellent save in tight. But with the netminder down on the ice, the puck squirted out to Zadorov, who blasted a slapper over Samsonov for his third of the season.

Things got physical in a pileup in front of the benches and Oliver Wahlstrom squared up with Keegan Kolesar, who scored the takedown.

Penalty trouble slowed the B’s momentum and prevented them from taking a two-goal lead into intermission.

John Beecher tripped Alex Pietrangelo from behind in the offensive zone and the Knights’ fourth-ranked power play cashed in, with a little help from the B’s. After winning the puck, Zadorov had plenty of time to clear it down the rink but he tried to make a pass up the middle that was picked off by Vegas. Eventually Mark Stone deflected home Shea Theodore’s shot at 15:09 to make it 2-1.

Brandon Carlo was also nabbed for a questionable roughing penalty later in the period but the B’s were much more deliberate in killing that one off.

The game was not trending well for the B’s in the second period. Vegas (16-6 shot advantage in the second) was establishing dominance in the B’s end and needed Swayman to come up with a couple of big saves.

The first one came at 11:45 when Pavel Dorofeyev was all alone at the bottom of the right circle but Swayman snared the 22-goal goal scorer’s hard wrister.

Then after Hertl deked through Charlie McAvoy, Swayman came up with a big stop on Hertl’s backhander.

But then the B’s, who’d spent precious little time in the Vegas end, regained their two-goal lead at 15:07 off a flub from Samsonov. The netminder came out to play the puck behind the net but he whiffed on his shovel attempt. Pastrnak pounced and fed Geekie out from for his 17th of the year.

As has so often happened with the B’s this year, however, they couldn’t close out the period. With just 34 seconds left in the period, Swayman could not handle Zac Whitecloud’s nothing shot from the point and it leaked over the line before Andrew Peeke’s attempt to yank it off the line was not successful.

“I had a good angle on it. I gloved it, had a motion going towards me and I think it slipped through and unfortunately it went past the goal line,” said Swayman.

It was a crushing goal.

Then at 4:56, the inevitable Vegas equalizer happened. Off the rush, both Wahlstrom and McAvoy went to Jack Eichel, leaving a lot of open ice. After taking the Eichel feed, Theodore made a terrific feed to a wide-open Dorofeyev at the bottom of the right circle and he didn’t miss this time.

“We had a forward and a D go to one guy, so we duplicated. We made a mistake there,” said Sacco.

The B’s appeared to get the go-ahead goal — oh so briefly — at 10:17 when Zadorov’s point shot got by Samsonov, but it was immediately waved off for contact with the goalie by Marchand.

But there would be worse things to come for the Bruins.

Now most of the team has two weeks off before the final 25 games.

“It’s do or die for us. We wasted the last two games, four points and it could cost us. We’ll see,” said Zadorov. “There’s no quit in this room. We have to come ready and compete.”