The Pens won 5-2 on the road thanks to goals from five different players. They were made to work for the win though, as Bryan Rust's opener was cancelled by Paul Cotter's equaliser.
From there, Pittsburgh got the upper hand in the goals department. Thomas Novak and Yigor Chinakhov scored nine seconds apart to make it 3-1, and while Jack Hughes halved the deficit before the end of the second, Evgeni Malkin and Erik Karlsson added third-period goals to give the Pens the win.
Having picked up a third successive victory, the Penguins were the fifth team in the Eastern Conference to lock down a playoff spot. The Devils, already eliminated from contention, lost for the third time in four games.
Also winning on Thursday were the Montreal Canadiens, who edged the visiting Tampa Bay Lightning 2-1 at the Bell Centre. The night was particularly special for Cole Caufield, who opened the scoring in the second period with his 50th of the season.
Darren Raddysh found the leveller for the Bolts with a little less than two minutes left in regulation. Many thought that there would be extra hockey in Quebec, until Juraj Slafkovsky netted what proved to be the winner with 64 seconds left.
With their 10th victory in their last 11, the Habs are still looking to top the Eastern Conference. They sit four points off the Carolina Hurricanes, who won their game 7-2 away to the Chicago Blackhawks. Montreal also jumped ahead of Tampa for third in the conference, the latter having lost for the third time in a row.
Elsewhere, the Ottawa Senators continue to cling to the final postseason berth in the East thanks to a 5-1 defeat of the Florida Panthers. Fabian Zetterlund scored twice for the Sens as they near one of the wildcard places.
The New York Islanders and Detroit Red Wings kept within touching distance of the wildcard spots thanks to wins of their own. The former got past the Toronto Maple Leafs 5-3, while the latter topped the Philadelphia Flyers 6-3.
Detroit's win was particularly important as they defeated a fellow play-off hopeful. Dylan Larkin scored a hat-trick for the Red Wings as they chose the perfect time to snap a three-game losing skid. They are still a point off from the Flyers with three games left.
The Buffalo Sabres shut out the Columbus Blue Jackets 5-0 at home to increase their hopes of topping the conference, while also damaging the Blue Jackets' hopes of making it through.
In Utah, the Mammoth got past the Nashville Predators 4-1 to solidify their chances of making the postseason. The Predators' loss adds more pressure to them as they are just above the line.
Having won the Western Conference, the Colorado Avalanche clinched the President's Trophy, with a 3-1 success over the Calgary Flames.
Gabriel Landeskog and Martin Necas were the first two scorers for the Avs as they were well on their way to another win.
They did concede with 2:52 left in the game to make it 2-1, only for Nathan MacKinnon to score an empty-netter to give the Avalanche another win.
It was the 46th win of what has been a remarkable year for Colorado. They are seven goals away from 300 on the year, having let in just 198 with four games left.
Other scores
St. Louis Blues 2-3 Winnipeg Jets
Dallas Stars 5-4 Minnesota Wild
Anaheim Ducks 6-1 San Jose Sharks
Seattle Kraken 4-3 Vegas Golden Knights (after shootout)
Los Angeles Kings 4-1 Vancouver Canucks