BOSTON — Before the puck even was dropped Saturday night, you had a feeling things were going to be different.

With an extra hour-plus to get lubed up and Rob Gronkowski waving the banner before the game, Bruins fans were full-throated and ready to go.

And then all you had to do was watch the opening faceoff to know the Bruins themselves were going to follow suit. The puck had not even hit the ice before Chris Wagner started in with a shove on Zach Hyman. And it didn’t stop until the Bruins walked out of TD Garden with a 4-1 victory, tying the Eastern Conference quarterfinal series at one game apiece.

This one not only felt like the Bruins at their best this year, it felt like a throwback to 2011. It was that intense, that visceral, that violent. And there were casualties. Torey Krug was launched backward and head first into the boards by Jake Muzzin late in the second period and did not return, and fellow defenseman Connor Clifton left midway through the third period after a hit by Nazem Kadri. And for his encore, Kadri – suspended for three games during last year’s first-round series – lost his mind again, cross-checking Jake DeBrusk in the face for a five-minute major with 5:57 left. That essentially ended the game, and quite possibly Kadri’s series.

In the middle of it all was David Backes, providing just the right dose of mayhem.

Bruins Coach Bruce Cassidy rectified what looked like a tactical error in leaving out Backes from the Game 1 lineup and inserted the veteran forward for Game 2 after what best could be described as a tepid performance in the opening-game loss.

And wouldn’t you know it, Backes helped give the Bruins a lead they never relinquished, assisting on Charlie Coyle’s goal early in the first period.

“He did it from the start,” Cassidy said. “It was his line that created the loose-puck turnover on the first goal. I think he recognized what he needed to do. He watched the game from up top the other night. There was something we were lacking. We addressed it. We needed him to do it, we needed other players to do it. He dragged other people into it. Jake DeBrusk, David Pastrnak had some great hits. Pasta’s first hit, he got called for (charging), but I thought it was a great hockey hit. So good for him.

“(Backes is) a leader. He does that. He’s been through these playoff battles. He did his job and then some. And we needed it.

“That game on Thursday, again, I don’t want to look back and say ‘woulda, shoulda, coulda.’ We’ve addressed that as a staff. We didn’t do a good enough job on Thursday, and I thought we corrected some of those things. The players executed much better, and I thought a lot of it had to do with that physicality that Backes brought with us.”

With less than five minutes gone, the Bruins already had set the tone with big hit after big hit. When Toronto defenseman Nikita Zaitsev went to retrieve the puck behind the Maple Leafs net, he saw Backes coming toward him and tried to avoid a hit, but Backes grabbed the loose puck and sent a backhand pass out to Coyle for a goal that put the Bruins up 1-0. Backes said he fanned on the pass, but the result was perfect.

“I think it had some special sauce on it,” Backes said with a smile. “(Coyle) was probably our best player in Game 1. He found the slot, found the looks, and the law of averages owed him one.”

Through the first two periods, Backes played just 6:45, but he found a way to pack seven hits into that brief ice time, which stood up as the game high for hits.

But Backes brings more than that, said Wagner, who had four hits of his own after a subpar Game 1.

“I thought he hounded pucks great and he was physical. And we expect that from him,” said Wagner, whose line with Noel Acciari and Joakim Nordstrom shut down the Hyman-John Tavares-Mitch Marner line. “But what you guys don’t see is, on the bench, he’s a loud voice. A lot of guys have echoed that, but it’s true and we respect him a lot for that.”

Backes didn’t know for sure he’d be in the lineup until Saturday morning.

“I was looking forward to this game ever since I was told I wasn’t going to be an active participant in Thursday’s game,” Backes said. “I got to channel that, I think, in the right way, in a constructive, controlled manner, and was able to make a little bit of an impact tonight.”

There still is some dust to settle from this one. The health of Krug, DeBrusk and Clifton could be big determining factors in this series, as will the status of Kadri, who is suspended for at least Game 3 and could face a longer suspension, pending a hearing with league officials on Monday.

But the Bruins could only win one game at a time Saturday night to get back into this series. And they did so in historically Bruins-like fashion.