Bergeron scored a power-play goal at 9:31 of the first period to give the Bruins a 1-0 lead. Brad Marchand skated toward the high slot and drew a couple of defenders to him before hitting Bergeron on a backdoor cut to the right side of the slot.
Marner tied it 1-1 at 16:44 after his initial redirection hit the post but the rebound went back to him at the right side of the net.
Marner scored shorthanded on a penalty shot at 2:47 of the second period for a 2-1 Toronto lead. He drew the penalty after stripping the puck from Jake DeBrusk at the Toronto blue line, getting taken down from behind by DeBrusk on a breakaway. Marner became the fifth player to score on a shorthanded penalty shot in the playoffs.
"We know we're fast in this locker room," Marner said. "I think when we play right it's hard to stop us. Tonight we just wanted to make sure we were getting pucks in for the first 10 minutes. It made it hard on the defense. I thought we did a great job of that. Our four lines played very well tonight with our defensive core. Frederik again was unbelievable."
Nylander scored through Rask's five-hole with 1:35 left in the period to extend the lead to 3-1 after Kadri sprung him on a breakaway with a long pass.
"Well I saw him in stride and I just tried to get my head up," Kadri said. "And I knew I had to put a little bit of extra juice on it for it to get there. So he did a great job skating up ice and finishing the job."
Tavares scored into an empty net with 1:19 remaining in the third period for the 4-1 final.
"Sometimes you get … with some time off you get away from playing your style, you know, but I think maybe we thought it was going to be a little bit easier than it was out there," Bruins forward Brad Marchand said of Boston playing its first game in five days, the same as Toronto. "But we were trying to play too much of a controlled style, where that's not really our game. So we've just got to play a little faster."