The Florida Panthers celebrate after a 4-3 overtime victory over the Boston Bruins in Game 7 of their first-round playoff series Sunday in Boston. Michael Dwyer/Associated Press

BOSTON — The Boston Bruins are done, with a long offseason to think about their failure to capitalize on the greatest regular season in NHL history.

The Florida Panthers are moving on, thrown right into their second-round series against the Toronto Maple Leafs.

“Game 7. Overtime win. Against pretty much the best team in regular-season history. It’s unreal,” Panthers center Aleksander Barkov said after Florida beat Boston 4-3 to eliminate the record-setting Bruins from the playoffs. “For sure it’s up there, and it’s hard to understand right now. I don’t think we need to understand right now. We’ll understand later.”

Brandon Montour tied it with 1 minute left in regulation, and Carter Verhaeghe scored the winner at 8:35 of overtime. The Panthers won three straight after falling behind 3-1 in the best-of-seven series.

Boston, the Presidents’ Trophy winners with NHL records of 65 wins and 135 points, had not lost three in a row all season.

“The fact that we were able to do what we did after what they did all year … they’re an unreal team and the best I’ve played in my NHL career. The fact that we were able to beat them was crazy,” Panthers forward Matthew Tkachuk said. “Let’s be honest: Nobody in the whole world thought we were going to win that series except for the guys in that room.”

Sergei Bobrovsky made 33 saves for Florida, which advanced in the postseason for just the second time since reaching the Stanley Cup Final in 1996. They will face Toronto, which finished off the Tampa Bay Lightning on Saturday in six games.

“I don’t think you can find a harder team to play against than the Boston Bruins. They will test you,” said Florida Coach Paul Maurice, who improved to 4-0 in Game 7’s in his career. “The players here now have a shared experience of what hard is. … It will make us better for five years. That’s how hard it was.”

Boston rallied from a two-goal deficit to take a 3-2 lead, but Maurice pulled Bobrovsky in the final minutes and called timeout with 1:28 left to give his players a breather. Montour tied it with his second goal of the game.

Maurice, who was on the Winnipeg bench when the Jets eliminated Presidents’ Trophy-winning Nashville in the second round in 2018, admitted his confidence was waning.

“We’re down a goal with under two minutes to go against Boston. I wouldn’t bet everything, because the match doesn’t add up,” he said. “But when that goal goes in you go, ‘Ohhh, we’re going to win this game.’”

Verhaeghe won it on a wrist shot from the right faceoff circle that just made it under the crossbar.

That eliminated the Bruins, who became the second Presidents’ Trophy winner in five years to lose in the first round. No team with the best regular-season record has won the Stanley Cup since 2013, when the Chicago Blackhawks beat Boston.

“It was an honor to coach that group,” said Bruins Coach Jim Montgomery, who took over in Boston this year after Bruce Cassidy was fired. “I know we didn’t get to where we wanted. I get that. But their professionalism, their work ethic, their commitment to being pros, it was a joy to be around.”

Montour scored Florida’s first goal, and Sam Reinhart made it 2-0 early in the second period. David Krejci and Tyler Bertuzzi scored to tie it, and David Pastrnak gave the Bruins a 3-2 lead with a power-play goal 55 seconds into the third period.

Jeremy Swayman, making his first start of the series as a sub for likely Vezina Trophy winner Linus Ullmark, stopped 27 shots.

The game could be the last for Bruins captain Patrice Bergeron, who teased retirement last year but opted to return. He was the last Boston player to leave the ice, after a stick-wave to the crowd and one last hug with Brad Marchand.

Bergeron said after the game he will take some time to consider his future. The five-time Selke Trophy-winner missed the first four games of the series and played the last three with a herniated disc.

“Learned a lot from him this year,” Montgomery said. “Hopefully learn more from him next year.”