Dahlin had a goal and four assists, Tage Thompson had a goal and three assists, and Jack Quinn scored two power-play goals and had an assist for Buffalo, the No. 1 seed in the Atlantic Division, which scored seven straight goals to come back after trailing 3-1 in the first period to tie the best-of-7 series 3-3.
Ukko-Pekka Luukkonen stopped the 18 shots he faced after replacing Alex Lyon at 10:14 of the first, when Jake Evans’ short-handed goal put the Canadiens up 3-1. Lyon allowed three goals on four shots.
Evans had a goal and an assist and Arber Xhekaj and Ivan Demidov scored for Montreal, the No. 3 seed in the Atlantic.
Jakub Dobes allowed six goals on 33 shots before he was replaced midway through the third period by Jacob Fowler, who saved two of three shots over the final 10:02.
Game 7 is in Buffalo on Monday (7:30 p.m. ET; ESPN, SN, TVAS, CBC).
Dahlin quieted the capacity crowd for the first time when he gave Buffalo a 1-0 lead 32 seconds into the first period. The Sabres captain deked around Juraj Slafkovsky when he drove to the net from the left side before scoring with a backhand over Dobes’ right shoulder.
The Canadiens brought the crowd back to life when they roared back with three straight goals on their first four shots.
Xhekaj tied it 1-1 at 1:40 off a face-off. Evans drew the puck back to Xhekaj, who moved up from the right point to snap a one-timer that went into the net off the top of Lyon’s glove.
Demidov put Montreal up 2-1 with a power-play goal at 8:12. He one-timed Lane Hutson’s pass to drive a slap shot past Lyon from just above the right face-off dot.
Evans scored short-handed at 10:14 to push it to 3-1. He drove the right side on a 2-on-1 with Josh Anderson and shot past Lyon to chase the Sabres goalie from the net.
Luukkonen relieved Lyon and Buffalo rallied to score seven unanswered goals.
Jason Zucker cut it to 3-2 when he scored on a power play at 13:56. He drove to the right side of the net to put Josh Norris’ pass in stick side.
Zach Benson tied it 3-3 at 1:00 of the second period when he came out from behind the net to get to a rebound of Thompson’s deflection of Bowen Byram’s shot before sliding in a backhand..
Quinn put the Sabres up 4-3 with Buffalo’s second straight power-play goal on a one-timer from the right point at 10:54.
Konsta Helenius made it 5-3 at 12:59 when he one-timed a shot past Dobes from the right side on a 2-on-1 pass from Zucker.
Quinn scored his second power-play goal to make it 6-3 at 9:58 of the third period.
Fowler relieved Dobes but he was pulled for an extra attacker when Thompson scored into an empty net at 14:12 to push it to 7-3. Zach Metsa scored Buffalo’s fourth power-play goal at 17:49 for the 8-3 final.
