TORONTO — Max Domi’s celebratory fist pump could’ve knocked out Jake Paul, he was so enthusiastic with his uppercut.

Underachieving like most of his teammates, the winger’s 4-on-4, coast-to-coast solo rush split the Pittsburgh Penguins defenders and turned Brett Kulak inside out before his blocker snipe beat Stuart Skinner and sent the Toronto Maple Leafs into the holidays on a high note.

A monster game-winner in a game that needed winning, Domi’s third-period tiebreaker ended a 23-game stretch during which he had more healthy scratches (two) than goals on the board.

No wonder he was so jolly.

“That was nasty. Flyin’. Dipsy-doodle and put it in,” William Nylander admired. “A huge goal for us. A lot of fun to watch.”

On a Festivus matinee with plenty of children in the barn, Toronto’s locals were beginning to air their grievances as the home team’s 3-1 lead had been erased by a Penguins push and the NHL’s worst power play couldn’t find the twine.

But Domi’s strike was rejoiced by all. Veteran Chris Tanev described it as “a Christmas present” in his return game.

A pair of empty-netters wrapped a bow on a tidy 6-3 victory.

“It’s exactly what we needed,” Domi said.

The egg nog should go down a little smoother.

“It’s a boost and gonna have a better Christmas, I guess,” coach Craig Berube said. “If you like Christmas.”

Despite going 0-for-3 during last week’s road trip, a nail-in-the-coffin stretch for assistant coach Marc Savard, the Maple Leafs had been playing progressively better.

Where they sit in the standings, however, leaves them needing a string of W’s long enough to wrap around the ol’ Douglas fir.

“We’re all judged by our results,” general manager Brad Treliving said, explaining his thinner bench. “It’s not lost on us where our team is at. We live it every day.

“The guys wear it. They care. And when you’re going through a difficult time, nobody wears it more than the people that are living it.”

Nobody was wearing William Nylander’s 11-game goal drought more than the Bearded One himself. The superstar looked as lost as we’ve seen him Sunday in Dallas.

So, it was impactful for the result and the confidence that No. 88 exploded for two goals and two assists Tuesday.

Yes, the Leafs were gifted some breakaways (Steven Lorentz got a three-whacker!) and Pens defenceman Parker Wotherspoon smashed a Matias Maccelli centring pass into his own net, but Toronto earned its breaks.

“We scored tonight,” Berube said. “That’s the difference.”

Had the Leafs fumbled another multi-goal lead, well, this game could’ve played out like a reboot of The Nightmare Before Christmas.

But they dug in, Domi broke the tension, and goalie Joseph Woll held fort.

“It’s kind of nice to have a little mental reset, especially with what’s going on,” said Lorentz, before ducking out to meet family. “We’ll take two points right now any way you can get it.”

Nah, they won’t need a gift receipt for this one. 

“We’re sticking together in here, and we believe in each other, and we believe in this group,” Domi said. “Tonight showed that. 

“Regroup, have a nice break with the families, and come out here swinging.”

• Little surprised to see Tanev — sidelined with an undisclosed head/neck injury since Nov. 1 — make his return in the final game before Christmas, but he got clearance from doctors Monday and decided to go.

“I think I played, like, half a game in nine weeks. So, it’s not fun. Definitely the longest stretch in my career I haven’t played. So, it’s definitely a lot of ups and downs. Just try to grind through it and stay positive. And I was extremely happy to be back on the ice,” Tanev said.

“They’re not going to let me play if they know something catastrophic is gonna happen, but obviously there are things that could happen.”

Tanev, understandably, was a touch rusty. 

He made a dangerous giveaway into his own slot — “gave someone a Christmas present in front,” he quipped — but finished with a plus-1 rating and a couple blocks. Encouraging for the group to have him back.

“He’s the ultimate pro. He goes out there and he empties the tank every shift. He does the hardest thing; he eats pucks for breakfast, lunch and dinner,” Domi said. “Off the ice, his leadership and his experience, it just calms our whole group down, gives us a lot of confidence.”

• In wake of Marc Savard’s firing, Derek Lalonde has been charged with leading power-play meetings, but PP decisions will be made as a staff. Treliving did not rule out the possibility of making an outside hire.

“I don’t think we’re turning the page right now on the season,” Treliving said. “We’re not here waving the white flag.”

The Maple Leafs got two power plays Tuesday and loaded ’er up — with one exception. Passer Matias Maccelli subbed in for Matthew Knies.

Maccelli took a slashing penalty 5-on-4, and Toronto went 0-for-2.

• Brad Treliving: “Auston has not asked for a trade.” 

• Sidney Crosby’s setup of Bryan Rust’s first-period breakaway goal marked his 1,080th assist and pushed him past disher Adam Oates for eighth most all-time. Next up: Joe Thornton (1,109).

The Penguins’ new all-time leading scorer’s assault on the record book continues.

• Loving these no-whites sweater matchups, which the NHL has termed “colour rush” games. More, please.