TORONTO - Mitch Marner scored the only goal of the shootout as the Toronto Maple Leafs fought back from 2-0 and 5-3 deficits to defeat the Montreal Canadiens 6-5 in a wild NHL regular-season opener for both teams Wednesday.

After the Leafs and Canadiens traded chances in the 3-on-3 extra period, Marner moved in on Jake Allen and fired upstairs on Toronto's third attempt before Ilya Samsonov stopped Kirby Dach at the other end to seal it.

Auston Matthews, with the 300th, 301st and 302nd goals of his career for his eighth career hat trick, William Nylander, with a goal and an assist, and Noah Gregor scored in regulation for Toronto.

Samsonov made 19 saves in regulation and overtime.

John Tavares had three assists, while John Klingberg, in his first game with the Leafs, chipped in with two.

Alex Newhook, with two, Cole Caufield, Jake Evans and Jesse Ylonen replied for Montreal. Allen stopped 37 shots. Dach added two assists.

Trailing 3-2 early in the third period after conceding that two-goal edge, the Canadiens got even at 4:25 on a power play when Caufield's shot hit the stick of defenceman T.J. Brodie.

Montreal then went back in front just 1:22 later when Newhook, acquired from the Colorado Avalanche in June, tipped a point shot past Samsonov moments after the Toronto goaltender robbed Dach.

Ylonen made it 5-3 at 11:55 when he jumped on a turnover by Leafs defenceman Timothy Liljegren and roofed a backhand.

But Matthews scored his second of the night with 4:32 left in regulation with Samsonov on the bench when he beat Allen from a tough angle before completing the hat trick with 1:07 remaining on the clock to send Scotiabank Arena into a frenzy.

Leading 2-0 early in the second period, the Canadiens appeared to go ahead by three on a power play, but Caufield's effort was wiped off the scoreboard when Toronto head coach Sheldon Keefe correctly challenged for offside.

That completely flipped the script - at least momentarily.

The Leafs cut the deficit in half at 7:41 when Gregor, who earned a job in training camp on a professional tryout, snapped a shot past Allen's glove.

Toronto, which advanced in the playoffs for the first time in nearly two decades last spring, tied it on a power play at 14:51 when Matthews fired past the Montreal netminder to become the fifth player in franchise history with 300 goals.

Nylander hit the post before Matthews equalized, but found the scoresheet with 44.5 seconds left in the period when he blasted home a one-timer to give the Leafs their first lead.

Toronto centre Fraser Minten made his NHL debut on the third line between fellow rookie Matthew Knies, who played 10 regular-season and playoff games last spring, and Calle Jarnkrok.

The Leafs, who lost to the rebuilding Canadiens in last season's curtain-raiser, are hoping for a better start in 2023-24 after combining to go 8-8-3 in October the last two campaigns as they look to challenge for top spot in both the Atlantic Division and Eastern Conference.

Expected to once again be in tough in an ultra-competitive division, Montreal went ahead 1-0 at 3:01 of the first when Brodie fell at the offensive blue line and Evans raced in alone on a breakaway.

Toronto winger Ryan Reaves, who pointed to his biceps during pre-game introductions, threw a couple of big hits as the period wore on, including one that led the Leafs' new tough guy to drop the gloves with Arber Xhekaj.

Montreal made it 2-0 just 70 seconds into the second when Newhook finished off a pretty 3-on-2 for his first with Montreal.

DOMI'S DEBUT

The son of former Toronto enforcer and fan favourite Tie Domi said before the game he hopes to chart his own path with the Leafs.

“My dad had a great career here,” Max Domi said. “Gave everything he had to this city.”

With the weekend trade of Sam Lafferty to the Vancouver Canucks, his dad's old No. 28 became available.

“Absolutely not,” Domi replied when asked if he was switching from No. 11. “That's my old man's number.”

MINTEN'S FIRST TASTE

The 19-year-old's poise and confidence stood out during camp as he climbed the depth chart to earn a spot.

“Try to stay present,” Minten said of how he deals with nerves. “You can't control what's going to happen. You can only control what you can do right now.”

Tavares recalled his first game with the New York Islanders in 2009.

“Remember the day feeling really long,” he said. “Then all of a sudden I thought I was going to be late … a lot of reflection.”

Keefe said Minten was having Thanksgiving dinner at defenceman Morgan Rielly's house when he got the call from general manager Brad Treliving informing him he would be starting the season with Toronto.

“Those are the kinds of things you love to hear,” Keefe said of how the veterans have welcomed the youngster. “Helps bring the group together.”

MONTEMBEAULT SITS

Allen, 33, got the start ahead of Sam Montembeault, 26, in Montreal's crease on opening night.

“Sam knows I believe in him,” Canadiens head coach Martin St. Louis said a few hours before puck drop. “He's going to be a big part of this team.”

UP NEXT

Toronto: Hosts the Minnesota Wild on Saturday.

Montreal: Hosts the Chicago Blackhawks on Saturday.

This report by The Canadian Press was first published Oct. 11, 2023.