Ryan: Bruce Cassidy went back to a lineup that first sparked hopes of a Cup run - a gamble that paid off in do-or-die Game 6

Bruce Cassidy had some decisions to make on Thursday morning.

Having to dictate matchups, juggle lines and orchestrate order from an NHL bench is a bit like trying to wrangle cats. When the puck is dropped and the biscuit (and bodies) start flying, there’s only so much one can do.

But with his club on the brink of elimination, Cassidy needed results, and fast. And amid the litany of tweaks and toggles that Cassidy and his staff needed to sort through, one lineup switch seemed rather obvious. 

With last change back in Boston’s favor, Cassidy and the Bruins had every reason to keep that potent top line of Patrice Bergeron, Brad Marchand and David Pastrnak intact.

The rationale was sound — if not painfully obvious. Aside from the fact that the potent trio combined for a casual 10-point outburst in last Sunday’s Game 4 victory, this grouping has been one of the few dependable conduits of 5v5 offense in this series. 

Entering Thursday’s potentially decisive Game 6, the Bruins had only scored six goals at 5v5 play against Carolina. The 63-37-88 grouping was responsible for four of those tallies — with the B’s outscoring the Canes, 4-1, and holding a 22-10 edge in shots on goal over their 28:37 of ice time. 

And with home-ice advantage allowing Cassidy to play keep-away when it comes to Bergeron and Carolina’s shutdown line of Niederreiter-Staal-Fast, Boston’s bench boss would have been absolutely justified in relying on Boston’s O-zone cheat code in order to extend this season for just a few more days.

But instead, Cassidy opted to shake things up. 

Rather than rely on the top-heavy lineup that has brought Boston plenty of good fortune for years (up until those pivotal moments of failed Cup runs), Cassidy went back to a forward group that he scribbled onto the whiteboard in the B’s dressing room plenty of times this year.

If the Bruins were going to falter on Thursday night against Carolina, they were going to go down swinging with the same lines that first helped get them to this point by way of a second-half surge from January-March. 

They were going to rely on a balanced top-six unit — hoping that Jake DeBrusk would regain his scoring touch next to Marchand and Bergeron and resemble the high-energy winger that lit the lamp 18 times in his final 34 regular-season contests.

They were going to lay it on the line with a second line of Taylor Hall, Erik Haula and Pastrnak — an unlikely concoction of high-end skill and a journeyman pivot that provided dependable scoring down that final stretch of an 82-game marathon.

And with just one loss standing between the B’s and a long (and likely painful) offseason, Cassidy deployed a third line of Trent Frederic, Charlie Coyle and Craig Smith — a puck-possession unit that so often landed punches early for this club when it was accruing points at a steady rate.

Sure, the Marchand-Bergeron-Pastrnak line represented the safest bet when it came to doing damage against the Hurricanes. 

But with their backs against the wall, Cassidy and the B’s opted to go out on their terms. 

And that faith in this usual cast of cohorts was rewarded. 

“Whatever he puts up on that board as far as lines ... you just got to do your job, no matter who you're playing with,” Charlie Coyle said of Cassidy’s lineup reshuffle. “Try to create something and do it the right way, no matter what. But I think having that lineup that we had, we're more familiar with one another. And you could tell.”

Marchand might have broken a 0-0 deadlock in the second period (Boston’s first instance of scoring first in nine games against Carolina), but the B’s finally received that long-awaited secondary-scoring salvo as the night progressed — with Coyle, Haula, Derek Forbort and Curtis Lazar all lighting the lamp in Boston’s season-extending Game 6 victory at TD Garden.

“Today was more about how we've been successful earlier in the year. We got ourselves back in the series. … So let's get back to the group, including Frederic, (Hampus) Lindholm coming in helps. But that was the main reason,” Cassidy said of the reasoning behind his lineup switch.  “'This is what we had success with, fellas'. We walked through why we're good. Certain parts of the game, our D-zone coverage had to be better, our shot blocking, our sticks in the lane to take away some of their offense and those four lines have all done it and done it well. So that was the task in front of them.”

For the first five games of this first-round series, Boston’s malfunctioning second line was a particularly sore spot in the club’s collective attack. 

After scoring 19 points over his final 19 games of the regular season, Haula entered Thursday with just two helpers etched into his stat line against Carolina. Hall, while generating some looks on the man advantage, found his O-zone creatively stagnated without having another all-world talent in Pastrnak to play off of.

But the reunited Hall-Haula-Pastrnak line picked a great time to finally snap their scoring lull, with Haula deflecting a slick feed from Charlie McAvoy to give Boston a 3-1 cushion in the third period — less than four minutes after Andrei Svechnikov halved the B’s advantage with a short-side snipe earlier in the frame.  

"Probably one of the best things we did tonight was respond after they made it 2-1,” Cassidy said of Haula’s goal. “Earlier this year, we'd have to fight through that longer. Right away, we came right back down, played the right way — managed the puck, got a puck back and scored the next goal. ... That's playoff hockey. We needed some guys to step up and score. We got it tonight.”

Coyle’s tally earlier in the game might have been on the man advantage, but it was the type of sequence that should earn plenty of praise in Friday’s video session — with the big-bodied pivot fighting down low and putting himself in the areas of the ice where skittering pucks are just asking to be snapped into twine.

And on a fourth line of Nick Foligno, Tomas Nosek and Lazar — those draining forechecking shifts that come with their job description were finally rewarded by way of Forbort’s tally from the blue line, along with Lazar’s empty-netter at 15:43.

Cassidy’s gamble was not just a validation of the combinations that delivered for the B’s countless times during the regular season. It was a necessary exercise, given what will await the B’s down at PNC Arena on Saturday.  

With last change now wielded by Rod Brind’Amour and the Canes, Carolina has the means to snuff out Boston’s top line at 5v5 play in Marchand, Bergeron and DeBrusk.

Had Boston won Thursday’s game in a similar fashion as Game 4 (depending on 63-37-88 as your get-out-of-jail-free card during spurts of O-zone struggles), one could envision a script similar to Game 5 playing out on Saturday — with the B’s getting a rude awakening when asked to rely on their depth for tangible offensive production.

But it’s safe to assume that collective dread has waned some in the aftermath of Game 6. 

If the Bruins are going to escape Raleigh with that sought-after victory, it’s going to come down to an entire lineup pulling on the rope to accomplish said endeavor.

An entire roster that, when given a chance to prove themselves once again, gave their season new life on Thursday night at a raucous TD Garden. 

“You change lines for a reason throughout the course of the playoffs,” Cassidy said. “You hope you make the right call for the right reasons and tonight it worked out for us. We'll do what we have to do up in Carolina in Game 7."