What we learned: Bruins struggle with discipline, PK

Eventually, the Boston Bruins knew they’d encounter their first off-night of the season.

Those odds of their first shaky outing increased ahead of their tough seven-game stretch. They appeared ripe for a rough performance against the Tampa Bay Lightning on Monday but overcame a rough opening 10-minute stretch to down one of the NHL’s elites on a night where Patrice Bergeron tallied his 1,000th career point.

Jim Montgomery’s squad took their historic early-season momentum down the Florida coast for a Thanksgiving-eve tilt with the Panthers. This time, the Bruins hit a wall.

Spencer Knight stymied the Bruins with multiple quality stops en route to a 37-save outing.

The B’s scored twice in 5-on-3 situations behind tallies from Charlie McAvoy and David Pastrnak, yet found themselves shorthanded more often than not.

The opportunistic Panthers pounced, scoring three times in seven attempts with the man advantage. On the first attempt following a questionable tripping call on Charlie Coyle, Sam Reinhart put Florida ahead 1-0 after a Hampus Lindholm misplay created a 2-on-1 situation in front of Jeremy Swayman 1:49 in.

Aleksander Barkov and Matthew Tkachuk extended Florida’s lead to 4-1 with their power play tips some 10-plus minutes after Anton Lundell notched the go-ahead goal following a Jakub Zboril turnover at even-strength.

With their seven trips to the box, Montgomery did everything he could to get the Bruins back within distance, from jumbling his lineup to pulling Swayman for an extra attacker for a 5-on-4 stint midway through the final frame. But the Bruins couldn’t overcome their shortcomings as Aaron Ekblad sealed Boston’s fate in the third with his empty-net tally.

Here’s what we learned as the Panthers snapped Boston’s seven-game win streak following their 5-2 win in Sunrise.

Boston’s penalty kill has hit a rut without Derek Forbort

Forbort provided significant support for the Bruins and their thriving penalty kill during the first month of the season.

The Bruins have relinquished nine power-play goals in their 43 attempts without Forbort since Nov. 1. With Forbort in the fold, the Bruins’ shorthanded unit had killed 30 of 32 attempts.

“With that responsibility, I think it gets split up with fresh guys on the ice who are in another situation as well that can go out there and make it hard on the other team,” Carlo told reporters afterward. “He’s definitely a big [peantly] killer, and we look forward to having him back.”

The last week, in particular, has been the biggest of sore spots. Wednesday marked the fifth straight game where the Bruins allowed a power play goal. Over that stretch, they’ve given up eight goals in 23 attempts, marking a paltry 65.2 percent success rate.

A quartet of Boston’s defensemen and a pair of forwards usually on the ice in shorthanded situations, entered the sin bin. That development forced Montgomery to alter his penalty kill lineup at certain junctures.

Forbort joined the team on their recent trip to Florida for skating sessions. The Bruins will have to make due on what they have to overcome this current PK rut. Until then, they’ll need to find a way to establish more time skating in 5v5 and power play situations.

The Bruins struggled with discipline.

Brad Marchand and company may have found themselves on the wrong end of the penalty spectrum amid an off-night from the officiating crew. But the Bruins wouldn’t use the refs as a proverbial punching bag during their postgame comments.

And indeed, the Bruins earned some of the trips to the box following ill-timed penalties. Their worst moment came following Pastrnak’s power play marker with a chance to pull within striking distance with Eetu Luostarninen still serving his double-minor for high-sticking McAvoy.

As the Bruins attempted to regain entry into the attacking end, Marchand found himself at center ice running interference on Sam Bennett. Instead of creating a few extra chances with the time ticking on Luostarninen’s penalty, the Bruins found themselves in a 4-on-4 scenario for a few minutes before embarking on another penalty kill.

“We’ve been undisciplined this year,” Marchand said to the press after committing his first penalty of the season. “And it bit us in the butt tonight.”

The 17-3-0 start may mask some deficiencies in Boston’s historic early-season performance. But Wednesday’s loss highlighted a significant area of concern with the frequent trips to the box.

The Bruins rank seventh in penalty minutes with 228. They also sit tied for second with the Coyotes and Oilers for most times shorthanded at 77.

Even against a recently struggling power play of late, the season-long trend didn’t bode well against the offensively-skilled Panthers.

“Not a situation that you want to be in. But ultimately, as long as they’re hard penalties and not the stick penalties — tripping and things like that — then we can live with those,” Carlo added. “But we got limit [the number of penalties]. Absolutely.”

The defensive coverage was a little too loose.

Even as a handful of players fought the puck at times, the Bruins encountered few to little issues generating high-danger looks against Knight. Down the other end of the ice, they struggled to support their netminder.

Granted, most of the defensive issues came on the penalty kill. But Brandon Carlo and company felt they could’ve layered up a little more to help Swayman out.

“I don’t think necessarily that they were doing anything special. I think it was us running outside of position and not being responsible in certain zones. Unfortunate that a couple of those ended up in the back of the net,” Carlo said.

“Our goalies go out there and battle every night for us, and they expect the same from us. It’s not that we weren’t giving him effort. But, there’s situations where you hate to see that… where pucks are going in the back of the net for situations where he’s not being helped out.”

Carlo was on the ice for two of Florida’s power play markers. The Bruins only allowed one goal at even strength yet struggled to clear pucks away from prime scoring areas, allowing the Panthers to generate a handful of secondary looks on tips and rebounds.

Swayman didn’t have his sharpest night, arriving late on certain shot attempts and at times failing to secure the short-side post as seen with Tkachuk’s tally.

He hardly needed to shoulder the blame on the three other goals — sans Ekblad’s empty-netter — that found twine. Regardless, Swayman netminder showed initiative when discussing the Tkachuk tally with the press.

“Their tendency was to bump [the play] to the middle, so I wanted to stay on my feet. But obviously, he read it well, and one that I definitely want back, and I learned from it,” Swayman said. “I’m not going to let that happen again.”

Swayman and the Bruins hope Wednesday was a mere blip on the radar. They’ve recovered from their previous two setbacks against the Ottawa Senators and Toronto Maple Leafs. And they hope to continue their bounce-back trend Friday against the Carolina Hurricanes in the first meeting since last year’s first-round playoff series.