BOSTON — After three consecutive days of practice that saw the returns of Claude Giroux, Ivan Provorov, Travis Sanheim, and Travis Konecny from COVID protocols, the Flyers may have gotten well, but they didn’t get well enough.

The Bruins, on the second night of a back-to-back, came out on a mission the moment the puck dropped in their 3-2 victory over the Flyers at TD Garden. The Bruins found their offensive firepower in winger David Pastrňák, who went into Thursday night’s contest averaging 1.17 goals per game against the Flyers. Pastrňák fired home a hat trick, including two first-period goals, and led the team with eight shots on goal.

“[The first period] was definitely our worst period in a long, long time,” winger Cam Atkinson said. “I’m not sure if the time off, guys haven’t played in a long time coming off of COVID protocol, but obviously no excuses. We knew that they’ve played a lot of hockey as of late. We did the exact opposite of what our game plan told us to do.”

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Meanwhile, despite evening the score in the second period, the Flyers struggled in the shot differential game, a season-long trend. The Bruins outshot the Flyers, 36-27, and finished with 12 high-danger scoring chances to the Flyers’ six, according to Natural Stat Trick.

Goalie Carter Hart attempted to keep the Flyers in the game in the third period, as he made seven saves, some of the spectacular variety. (Hart finished with 33 saves.) But the Flyers couldn’t find the back of the net, even on a 5-on-3 advantage at the end of the third period. In turn, the Bruins handed the Flyers their sixth straight loss.

“I think that you look at a number of our games lately and we have spurts here and there,” interim head coach Mike Yeo said. “We aren’t capable of sustaining momentum, sustaining play. Even when things aren’t going necessarily outstanding, you can’t let things go really bad. We have to do a much better job of that.”

A tale of the first seven minutes

Within the first six minutes of the first period, Pastrňák and the Bruins came out with jump as they established a 2-0 lead. The Bruins’ first tally came less than two minutes into the first period on a sequence of blunders as the Flyers’ attempted to clear their own zone — winger Jackson Cates mishandled the puck at the blue line, but when center Scott Laughton recovered it, his errant pass to Sanheim took a bounce off the boards and onto the tape of winger Taylor Hall’s stick. He tapped the puck to Erik Haula, who found Pastrňák in the slot. His wrist shot sailed past Hart to put the Bruins up, 1-0.

“They played last night, so maybe they were a little more jump early on,” Sanheim said. “Our execution wasn’t there. I thought we were a little sloppy and ended up costing us that first goal.”

The Bruins racked up goals while the Flyers racked up penalty minutes. After defenseman Nick Seeler was called for holding winger Anton Blidh four minutes into the second period, Pastrňák capitalized on the power play to put the Bruins up, 2-0. Just 20 seconds after the second Pastrňák goal, the Flyers responded with yet another penalty — a Provorov high-sticking call. Defensive errors and bountiful penalties had the Flyers playing on their heels right out of the gate against a Bruins team flying high after their 5-1 victory over the Montréal Canadiens the previous night.

Flyers find a pulse

After winger Tomáš Nosek was called for interference with the Bruins up 2-0 in the second period, the Flyers went on their second power play of the night. Over the course of their five-game skid heading into Thursday night’s game, the Flyers had gone 2-for-14 on the man advantage. Against the Bruins, the Flyers started off shaky, failing to register a shot on goal on their initial power play of the night in the first period . But their next attempt fared much better, thanks to the efforts of the second power-play unit.

Atkinson deflected Provorov’s wrist shot from the top of the right face-off circle, scoring on goalie Tuukka Rask, who was making his season debut, to cut the Flyers’ deficit to one. Seven minutes later, winger Joel Farabee flaunted his skill as he maneuvered his way through the neutral zone, past defenseman Charlie McAvoy at the blue line, and then slid the puck across the crease for winger Atkinson. The puck deflected off Atkinson’s skate and caromed back to Farabee, who backhanded it past Rask to tie the game, 2-2.

“We turned over a puck in the neutral zone and just attacked from there,” Farabee said. “I think we were quick. It didn’t give their D much time to set up, and we got by them. So really good play by Cam just to get a piece of it and let me get back to it.”

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Killer penalties

Sixteen seconds after Farabee scored the equalizer, the Flyers saw any potential momentum snatched away when defenseman Justin Braun was called for tripping. The Flyers were faring well on the kill, clearing the puck three times and allowing one shot on goal, but then Max Willman was called for hooking, giving the Bruins 48 seconds of 5-on-3 time.

The Bruins quickly made the Flyers pay for their lack of discipline, as Pastrňák completed the hat trick on a one-timer from the high slot. The goal marked Pastrňák’s seventh in his last four games. Now, Pastrňák has scored three hat tricks against the Flyers in less than a year.

“As opposed to maintaining momentum, we end up giving them all the momentum in that situation,” Yeo said. “And worse yet, we end up giving them the lead.”

What’s next

The Flyers return to the Wells Fargo Center on Saturday to face off against the New York Rangers at 7 p.m. (NBC Sports Philadelphia).

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