When the Bruins came out the three-day Christmas break, they exploded out of the gate, winning five of their first six games.

Perhaps their last vacation was a bit too long.

Starting a seven-game homestand after a 10-day break, the B’s were outplayed, outworked and out-thought by a .500 Calgary Flames team, taking a well-deserved 4-1 loss at the Garden.

The Flames were clearly the more ready team in the first 40 minutes and, after the B’s thwarted their own brief momentum with a mental mistake early in the third period, they left the Garden with a well-earned two points.

It was the Flames’ first game since they moved one of their big trade chips, Elias Lindholm, and on cue, one of the pieces that went back to Calgary was heard from quickly.

After Brandon Carlo was called for holding just 3:48 into the game, the newest Flame, Andrei Kuzmenko, got the visitors on the board at 4:20. Charlie Coyle was stopped by Jacob Markstrom on a partial shorthanded breakaway and then the Flames transitioned quickly. From the right wing, Kuzmenko beat Jeremy Swayman low to the glove side for a 1-0 Calgary lead.

Throughout the first period, Calgary looked like the team that was much less adversely affected by the All-Star break and bye week. They took away the B’s time and space all over the ice and, on the rare occasion they didn’t, the B’s simply flubbed the puck and missed easy passes.

Calgary took a 2-0 lead at 13:01 on a 3-on-2 rush. Nazem Kadri carried the puck through the middle of the ice and fed Connor Zary on the left wing. Zary got around and behind Kevin Shattenkirk, then tucked a backhander behind Swayman.

The B’s got an opportunity to get back in the game with 4:00 left when things got rough. Brad Marchand took an extra whack at Markstrom in the hopes of knocking the puck loose, to no avail. After the whistle, Marchand took a couple of shoves from the Flames in the area before Martin Pospisil came off the top rope with a crosscheck to Marchand’s face.

Marchand got two minutes for slashing and, after a review, Pospisil was handed a five-minute major and game misconduct.

But after the 4-on-4 ,the B’s could do nothing with the three minutes of power play time.

Understandably, coach Jim Montgomery put his top three lines the ol’ blender. While that approach rarely fails him, this time all it produced a few extended stays in the Boston zone wile groans turned into boos.

Toward the end of the period, the B’s tried to create some energy, but promising plays died on the vine and the B’s went into the second intermission still down two – and they were fortunate that they were still in striking distance, theoretically at least.

But the B’s looked like a different team to start the third. Charlie McAvoy hit the post early. Then the B’s got one power play, and then a 5-on-3 for 1:09 when Mackenzie Weegar took a double minor for a high-stick on Brad Marchand. On the two-man advantage, Pavel Zacha got the B’s on the board when he scored a deflected shot at at 4:14.

The B’s still had more three minutes of PP time left with Weegar still in the box but, in keeping with the night’s theme, they had a hand in their own undoing. The remaining 1:46 of the power play was wiped out when the B’s committed had too many men on the ice.

On the ensuing 4-on-4, McAvoy coughed up the puck to Jonathan Huberdeau on a breakout attempt and Huberdeau snapped it past Swayman to give the Flames their two-goal lead back.

That crushed any momentum the B’s had built.

After Coyle took a slashing penalty, local boy Noah Hanifin just about put out the Garden lights. The Norwood native carried the puck down the right side and slipped a backhander through Swayman’s pads at 9:44, a softy.