LAS VEGAS -- Jonathan Marchessault and William Karlsson have struggled to find the back of the net since Dec. 22, scoring a combined three goals over 12 games.
Vegas' dynamic top-line forwards topped that Saturday night.
Marchessault scored three goals for his second career hat trick and Karlsson got his 16th of the season to help lead the Golden Knights to a 7-3 victory over the Pittsburgh Penguins.
"Our first period we weren't necessarily happy; as a line we take a lot of pride playing well defensively and we gave a little too much chances, but we played better in the second half of the game," Marchessault said. "Hopefully (I) get going a little bit more here. It's definitely been a tough stretch. I just want to get out there and help my teammates."
Marchessault scored twice less than four minutes apart in the second period to give Vegas a 5-3 lead. His empty-netter with 21 seconds left in the game completed the scoring with the Golden Knights' first hat trick of the season and third in franchise history.
Shea Theodore, Max Pacioretty and Oscar Lindberg also scored as the Golden Knights improved to 16-4-3 at home this season. Marc-Andre Fleury, who spent his first 13 seasons with the Penguins, stopped 34 shots to earn his league-leading 27th victory.
"It was fun, it was busy both sides, I wish maybe there wasn't three goals going in the net," said Fleury, who also leads the league with 43 starts. "It's always weird (playing against Pittsburgh), I don't know when it will stop. Just weird to see these guys out there, guys I practiced with every day for (13) years. It's nice to win though."
Phil Kessel, Dominik Simon and Sidney Crosby scored for Pittsburgh, and Casey DeSmith finished with 28 saves.
Both goalies were exceptional against two of the more high-energy offenses in the league. All 18 Vegas skaters had at least one shot, while 14 of Pittsburgh's 18 had one shot.
"It's a great team that you're playing, you're playing superstars over there, you're playing Crosby and you're playing (Evgeni) Malkin and those types of players - that's the fun part of these games," Vegas coach Gerard Gallant said. "I like the way our team responded tonight and I like the way that we competed and battled. It wasn't looking good when it was 3-3.
"We got six goals against their goaltender but I thought he was outstanding. He made some great saves and I thought Fleury made some unbelievable saves too. They both played a great game. It could've been a 9-7 game for somebody."
The Penguins concluded their sixth of 11 back-to-back situations, after winning 4-3 in overtime at Arizona on Friday. Pittsburgh is 8-3-1 in back to backs, going 5-0-1 the first night and 3-3-0 the second.
Teams making stops in Arizona, then Vegas, are now 1-7 against the Golden Knights after playing the Coyotes.
The Penguins came out flying to dominate the start of the second period to erase a two-goal deficit with consecutive goals by Simon and Crosby inside the first six minutes to tie the score 3-3. Jake Guentzel, who has eight goals in nine games since the start of 2019, assisted on both goals.
But after Pittsburgh's would-be fourth goal was overturned when the NHL's Situation Room deemed Malkin kicked the puck into the net, things began to unravel, and the Golden Knights gained momentum off Marchessault's two goals.
"We just didn't play the game very smart; I thought the second period we were terrific, we climbed back into it, and then we end up giving up two goals late in that period that were avoidable," Pittsburgh coach Mike Sullivan said. "Give Vegas credit, they're a good team, they're hard to play against. But to a certain extent we beat ourselves."
NOTES: Alex Tuch, who assisted on Pacioretty's goal, leads the Golden Knights with 38 points (15 goals, 23 assists) this season. ... Malkin, who also assisted on Kessel's goal, is just two assists shy of reaching 600 for his career. ... Since being recalled from the Chicago Wolves on Dec. 19, Brandon Pirri leads Vegas with 13 points (8 goals, 5 assists), but had his four-game point streak end. ... The attendance was 18,511, for the second-largest regular-season crowd in the second-year franchise's history.
Pittsburgh: Hosts New Jersey on Jan. 28.
Vegas: Hosts Minnesota on Monday.
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