Pastrnak drilled a one-timer from a Charlie McAvoy relay past Jordan Binnington with just 1:47 left to secure the 2 points.

“What a crazy shift that was. There were a few looks that we had, and obviously McAvoy and Mason (Lohrei) did their thing and they kind of buzzed around and they kind of collapsed on the puck, which bounced to Pav (Pavel Zacha), I think he kicked it at him (McAvoy), and it came at me,” Pastrnak said, before bursting into laughter. “And I just shot it as hard as I could.”

Binnington leaned forward as if he’d squeezed it, but it was there.

It was the game-high 10th shot of the night and the team-high seventh goal of the season for Pastrnak, who led all forwards with 24:29 of ice time.

The Bruins (8-7-2) moved into third place with a two-goal gap but continued to push the pace despite losing top defenseman Hampus Lindholm to a lower-body injury late in the first period.

As that setback stared them down, the Bruins remained steely-eyed.

“They scored some nice power play goals in the second inning and we fell behind,” coach Jim Montgomery said. “But we talked about going with it for 60 minutes and playing the right way. And even though we still made a few mistakes in the third – because you’re going to make mistakes, it’s a game of mistakes – we kept fighting. We continued to play the right way. We got to the goal line and got some big goals.”

The Bruins evened things up with a pair of goals set up by their leaders.

First it was Pastrnak.

The crafty winger stole the puck and fired toward St. Louis. He waited patiently and then delivered a pass to Morgan Geekie, who beat Binnington under the right pad with a one-timer at 4:53 for his first of the season.

“It’s always nice to get the first one, especially when you get back into the lineup,” Geekie said. “So it’s okay. It helps a lot. Mentally things are going well.”

The equalizer came from McAvoy.

Brad Marchand dug the puck out of a group of skates and sent it back to the blue line, where McAvoy unleashed a backscratcher past Binnington’s glove side at 9:15.

“Great play by Brazz (Justin Brazeau) to present himself and then a little bit of puck luck that you need,” McAvoy said. “So it’s hard work, they won a fight with him and (Marchand), and then Marchy looked like he was going to shoot it and I just yelled at him as loud as I could that I wanted it, and a lot of patience from him to to turn, hear me open up, and feed me into a good spot and just get it past the first layer, get to the net.

From then on, the Bruins kept the pressure on, buzzing Binnington (27 saves) and keeping the Blues (7-9-0) in control until Pastrnak fired in the decisive goal.

The Bruins owned the first period territorially, but neither team could strike through the first twenty.

Boston suffered a demoralizing four-minute stretch that changed the momentum in the second.

Cole Koepke was called for high-sticking and the Blues made it stinging, with Brayden Schenn tapping in a rebound on Jordan Kyrou’s closing shot for a 1-0 lead at 9:24.

Just over a minute later, St. Louis returned to the man advantage when Pastrnak played Oskar Sundqvist.

Once again the Blues rubbed it in and doubled their lead.

This time it was an unmarked Sundqvist who cashed in a Dylan Holloway pass at the post to Jeremy Swayman’s left.

They were the first two power play goals the Blues had scored at home all season (nine games).

The energy the Bruins had been playing with was sapped and they floundered through the final eight minutes of the period.

The Bruins came out with renewed spirit in the third and finally solved the Binnington mystery. Meanwhile, Swayman (20 saves) kept the Blues from expanding their lead.

“You can really build on these things,” McAvoy said. “You have to do the right things in the future. But there are a few times a year when you win a game like this or something like this happens, you come back and find a way like we did tonight, and you can really build on that.

‘So you have to earn them. And we did that tonight, and we have to do the right things going forward. But this can certainly make a difference.”

Jim McBride can be reached at [email protected]. Follow him @globejimmcbride.