Slafkovsky scored three of the Habs' four goals en route to the 4-3 win in the first overtime game of this year's playoffs. Five of the games' seven goals came during a power play, with four of those being in a row to end the game.
He led all skaters with an 8.8 player rating for the game after becoming the first player in playoff history to score three power-play goals and the overtime game winner.
It was the first game in the modern era where the NHL saw a Stanley Cup Finals rematch in the first round of the playoffs. Montreal and Tampa had previously met in the 2021 finals.
After the Lightning came out firing right after puck-drop, it was still the Habs who got on the board first.
Josh Anderson got the puck wide open in front of the net and wristed it past Andrei Vasilevskiy to make it 1-0.
He is one of six Canadiens players who played against Tampa when the two teams faced off in the 2021 Stanley Cup Finals.
Tampa Bay would fail to convert on both of their power plays in the first period, despite outshooting the Habs 9-4.
Brandon Hagel would receive a two-minute minor for interference on Montreal's Kaiden Guhle.
But Tampa would enter the second period on their third man-advantage of the game after Guhle was whistled for a double-minor for hooking Brayden Point in the same incident.
Both teams would have two players each in the penalty box within the first minute of the second period after Tampa's Nikita Kucherov was given a two-minute minor for high-sticking, forcing a 4-on-4 for a minute before the Canadiens had a brief 5-on-4 power play.
Neither team would capitalize on any of their opportunities to start the period, but that would quickly change halfway through.
After an overturned goal call that kept the Habs at one on the scoreboard, Anderson would commit back-to-back minor penalties, leaving the Lightning with perfect opportunities to tie it.
Darren Raddysh would slap one home on the power play to tie it up before teammate Brandon Hagel gave the Lightning a 2-1 lead just 29 seconds later.
Both goals were assisted by Jake Guenztel, who recorded the fastest two points in franchise playoff history.
But the Candiens wouldn't let up.
Juraj Slafkovsky scored on the power play himself with 24 seconds left to go in the second as the Habs headed into the third period with two goals on just nine shots.
Anthony Cirelli would commit his first penalty of the game for an interference on Slafkovsky, who would get his revenge shortly after.
Slafkovsky would score his second power play goal of the game to give the Habs a 3-2 lead just six minutes into the third period.
He became the first Habs player since Thomas Vanek in 2014 to score two power-play goals in a playoff game.
But another power play just meant another Lightning goal to tie it all back up.
Hagel would score his second of the game to make it 3-3 with 11:02 left to go in the third. It would mark the third assist of the game for Guenztel and the second for Nikita Kucherov.
Guenztel became just the second player in Lightning history with three assists in a playoff-opening game, the first being Victor Hedman in 2021.
With 20.5 seconds left to go in the third, Guentzel would get the whistle for a minor for the game's fourth high-sticking penalty.
After not scoring in the remaining regulation time, the Habs went into OT with 1:40 left on the PP.
And, who else, but Slafkovsky to score the game-winner and complete the hat trick.
He became just the third person in Montreal Canadiens history to complete a playoff hat trick with an overtime goal, the others being Eric Desjardins (1993 Stanley Cup Finals) and Gerry Plamondon (1949 Stanley Cup Finals).
Slafkovsky also became the first Canadiens player since Rene Borque (2014) to put up a playoff hat trick, while also scoring the second-fastest overtime playoff goal in franchise history since Nick Suzuki (2021).