Cooley scored his first goal of the game to put Utah ahead 1-0 at 4:40 of the first period. After intercepting a pass from Karlsson, he skated through the high slot to the left face-off circle for a wrist shot.
"He's one of our top players who's supposed to be doing that," Sergachev said. "But I'm happy for him. He had a bit of a slow start, but he's going to show everyone what kind of player he is. ... When he puts it all together, he's what he is tonight."
Cooley then made it 2-0 at 14:11, splitting Karlsson and Pittsburgh defenseman Spencer Stastney, and racing to the net front for a wrist shot blocker side.
"I think 'Cools' was alright," Mammoth coach Andre Tourigny said. "He was OK. OK, his goals, it's part of it. It's his work ethic, his mindset, his body language, his decisions with the puck. It's where he tries to play with the puck. He was really good."
Karlsson cut it to 2-1 at 8:38 of the second period, stickhandling around Mammoth forward Nick Schmaltz for a wrist shot from the inner edge of the right circle.
Rakell tied it 2-2 with a short-handed goal at 10:59 of the third period, collecting the puck in the neutral zone after it got past Cooley at the point and scoring his third goal in four games on a wrist shot from the right circle.
"We battled hard to come back into it and get the lead," Penguins defenseman Kris Letang said. "But I think, overall, the performance was not there.”
NOTES: It was the 10th game in NHL history, in the regular season or the Stanley Cup Playoffs, where teams traded a go-ahead goal and game-tying goal in the final 30 seconds of regulation, and the first since the Philadelphia Flyers defeated the New York Islanders 5-4 on April 7, 2015. ... The hat trick was Cooley's fourth in the NHL and first since having four goals and one assist in a 5-1 win against the Vegas Golden Knights on Nov. 24, 2025. ... Mammoth defenseman Artem Duda recorded four shots on goal and one block in 15:27 of ice time in his NHL debut. ... Malkin, who is tied with forward Nicholas Robertson for the team lead with six goals, returned from missing a 3-2 overtime win against the Nashville Predators on Saturday because of an illness. ... Utah defenseman Andrew Peeke had one shot, one block and two hits in his 400th NHL game.