Panthers center Anton Lundell attempts a shot against Bruins goaltender Linus Ullmark and defenseman Hampus Lindholm during Game 6 of their first-round playoff series Friday in Sunrise, Fla. Florida tied the series at 3-3 with a 7-5 win. Wilfredo Lee/Associated Press

SUNRISE, Fla. — The team that posted the best regular-season record in NHL history is facing a team that needed to fight and claw all the way to the end just to get into the playoffs.

On paper, it was a mismatch.

On the ice, it’s going to Game 7.

The wild-card Florida Panthers – by prevailing in an absolutely bonkers third period – fended off elimination for the second time and sent the mighty Boston Bruins into a winner-take-all game. Matthew Tkachuk scored twice, Eetu Luostarinen put Florida ahead to stay with 5:38 left, and the Panthers won 7-5 on Friday night.

“Everyone’s rolling. Everyone’s playing. Everyone’s doing the right things,” Panthers captain Aleksander Barkov said. “It’s fun to be a part of this, for sure.”

The real fun comes Sunday: Game 7 in Boston.

“I’m going to enjoy the hell out of it,” Panthers Coach Paul Maurice said.

Barkov, Brandon Montour, Zac Dalpe and Sam Reinhart also scored for the Panthers, who got 30 saves from Sergei Bobrovsky. Reinhart closed it out with an empty-netter with 28 seconds left – the seventh and final goal of the third period, four of those by Florida.

Tyler Bertuzzi and David Pastrnak each scored twice for Boston, which got four assists from Brad Marchand and 26 saves from Linus Ullmark. Jake DeBrusk also scored.

Boston finished 42 points ahead of Florida in the standings, the biggest gap between playoff opponents in nearly 30 years. The Bruins had the best regular-season record in NHL history, and they had one-goal leads twice n the third period, but couldn’t hold either one of them.

Not even three power-play goals and one short-handed tally was enough to give Boston a series-clinching win.

“We worked all year to get home-ice advantage,” DeBrusk said. “And it comes down to a Game 7, where we’re up for elimination now.”

The game started along the exact sequence as Game 5 in Boston on Wednesday night: Florida took a 1-0 lead, Boston tied it, Florida took a 2-1 lead, Boston tied it, Florida took a 3-2 lead, Boston tied it.

Evidently, that’s when the teams decided a repeat performance was boring.

They combined for four goals in a span of 6:56 – this time, with the Panthers answering the Bruins.

“They’re a determined group,” Bruins Coach Jim Montgomery said of Florida.

Boston went up 4-3 on a power-play goal from Pastrnak, Dalpe tied it for Florida, DeBrusk scored short-handed for a 5-4 lead, and Tkachuk got his second of the night 27 seconds later to tie it again.

Less than 4 minutes later, Luostarinen made it 6-5 with 5:38 left. Boston pulled Ullmark twice with hopes of netting the equalizer, getting good looks at it in the final minute.

But Bobrovsky and Florida’s defense held firm, and Reinhart finished it off. To Sunday they go, with Florida on the brink of a surprise and Boston trying to avoid a collapse.

“We know that there’s going to be a war out there,” Ullmark said. “That’s how it is in the first round. It’s the toughest one to get by.”

AROUND THE RINK

It was captain Patrice Bergeron’s 1,463rd game with the Bruins, including the playoffs. That’s one behind New Jersey’s Martin Brodeur for 13th-most with one franchise. … Florida forward Ryan Lomberg (upper body) missed his second consecutive game. … Bruins center David Krejci (37) and defenseman Connor Clifton (28) had birthdays on Friday. Boston was 1-1 in Krejci’s previous birthday games, beating Tampa Bay in 2018 and losing to Ottawa in 2013. The Bruins shut out Buffalo on Clifton’s birthday last year.

BIG CALL

The biggest play of the night might have been made by someone on the Panthers’ staff armed with an iPad.

The Bruins appeared to take a 3-2 lead with 11:32 left in the second period on a goal by Brandon Carlo – except the play should have been whistled dead 10 seconds earlier. But Florida took a quick look and challenged the goal, claiming DeBrusk had been guilty of a hand pass to Bergeron in the corner to Bobrovsky’s left earlier in the play.

Officials eventually agreed, taking the goal off the board. Barkov scored for a 3-2 Florida lead about two minutes later. Maurice said John Congemi – one of the team’s video coaches – was the one who noticed the infraction.

RARE NUMBERS

It was the fifth time in Bruins’ history that they had at least three power-play goals and one short-handed score in a playoff game. Of the earlier four, two came in 1976, one in 1970 and the other in 1958.