(Photo credit: Morgan Tencza-Imagn Images)

Juraj Slafkovsky netted his hat-trick game-winner 1:22 into the postseason's first overtime as the visiting Montreal Canadiens stunned the Tampa Bay Lightning 4-3 on Sunday in Game 1 of their Eastern Conference first-round series.

After the Lightning's Jake Guentzel committed a high-sticking penalty with 21 seconds left in regulation, Montreal cashed in after the break as Slafkovsky took a pass from Lane Hutson and zipped the winner in Tampa, Fla.

It gave the 30-goal scorer his third power-play marker of the night as he became the first Montreal player to record a hat trick in the Stanley Cup playoffs since Rene Bourque in 2014 as the Canadiens wrested away home-ice advantage in the best-of-seven series.

'You've got to be able to play any position out there,' said Slafkovsky, the 2022 No. 1 overall pick who netted his goals from the left and right circles plus the slot. 'We just kind of rotate and find the open guy who can shoot it. We had so many chances. ... I'm happy with the results so far.'

Josh Anderson scored the other goal for the Canadiens while Cole Caufield and Nick Suzuki notched two assists apiece. Rookie goaltender Jakub Dobes made 20 saves.

The Lightning's Brandon Hagel scored on the man advantage and at even strength while Darren Raddysh scored on the power play. Guentzel posted three assists and Nikita Kucherov had two.

Andrei Vasilevskiy stopped 15 of 19 shots as Montreal went 3-for-5 on the power play.

'I had a problem with us,' said Lightning coach Jon Cooper when asked whether he had an issue with the officiating. 'Come on, we took four offensive-zone penalties. Just look at them. That's not overaggression, that's like, stupidity. A lot of them. So that was on us.

'That was a game that we just gave them an opportunity to win. This is the Stanley Cup playoffs. This isn't Game 62. So that is extremely disappointing in the way we conducted ourselves and the amount of penalties we took. ... There are no excuses. Nothing.'

Montreal defenseman Alexandre Carrier won a puck battle from his knees behind the home side's net in the first period, then Anderson took Carrier's feed and roofed the series' first marker at 13:24.

Just 12 seconds after another Anderson tally was waved off due to a high stick, Lightning defenseman Charle-Edouard D'Astous was sandwiched between hard checks by Jake Evans and Anderson. While Anderson was assessed a minor, D'Astous eventually got to his feet and was helped off but did not return.

Tampa Bay's offense took off from there.

Raddysh, a 22-goal scorer, rocketed a power-play tally at 12:15. Hagel found a puck to the left of the cage and lifted one in just 29 seconds later for the Lightning's first lead in the series.

During a late power play after Tampa Bay's Conor Geekie went off for high sticking, the Habs moved the puck quickly. Slafkovsky blistered a one-timer from the right circle with 24 seconds left in the second period to make it 2-2.

On another power play in the third, Montreal took its second lead on more nifty passing. Slafkovsky buried his second goal from the low slot at 5:56 off a feed from Caufield.

But Hagel matched it with a man-advantage tap-in two minutes later on Guentzel's third assist.

--Field Level Media