Coyle gave Boston a 1-0 lead at 18:35 of the first period. He took a drop pass from Danton Heinen at center ice, powered his way into the offensive zone and roofed a backhand from the edge of the left face-off circle.
Ullmark stopped all 15 shots he faced in the first. The Panthers had the first eight of the game.
“The start of the game, obviously, was [all] Ullmark,” Bruins coach Jim Montgomery said.
Lundell tied it at 10:33 of the second period when Nick Cousins’ low wrist shot from the point went off Lundell’s right skate and past Ullmark to make it 1-1.
Beecher put Boston back in front 2-1 at 11:14 on a backhand that slipped off his stick and was accidentally knocked in by Florida defenseman Oliver Ekman-Larsson on his diving attempt to keep it out.
Beecher, a rookie, has scored in consecutive games and has three goals this season. He had nine in 61 games for Providence of the American Hockey League in 2022-23.
“I don’t know what’s going on out there; it is kind of uncharted territory,” Beecher said. “It’s exciting. I am trying to help the team win as much as I can and if that means ending up on the score sheet, so be it.”