Downie scored two third-period goals to help the Penguins hold off the Tampa Bay Lightning in a 6-3 win at Consol Energy Center.
After Alex Killorn cut the Penguins lead to 4-3 with 8:42 left in the third period, Downie scored 34 seconds later to re-establish Pittsburgh's two-goal lead.
Sidney Crosby backhanded a pass to Downie between the faceoff circles, and Downie dragged the puck around Lightning defenseman Victor Hedman before getting a wrist shot past goalie Evgeni Nabokov with 8:08 remaining.
"I had a couple opportunities," Downie said. "I got lucky. I thought we played well, so it was a good night. … I felt a little heavy. The breath was hard to come, but after a couple shifts, it gets pretty easy."
Lightning captain Steven Stamkos said he was disappointed with Tampa Bay's inability to shut down Pittsburgh through the next shift after fighting to pull the game to within one goal.
"We started playing the right way," Stamkos said. "We skated. We made plays and we didn't turn the puck over. We came back and made it a one-goal game. That next shift is huge. They score a goal. So, not a good game by us tonight."
Penguins goalie Thomas Greiss also returned to action for the first time since being diagnosed with the mumps. He made 32 saves for his fourth win of the season.
Downie, who played on the top line alongside Crosby, scored his second goal of the game, seventh of the season, into an empty net with five seconds left.
Crosby had four assists. It was his second game with at least four points; he had five assists against the Buffalo Sabres on Nov. 8.
"I don't think it matters who's playing with who when we play the right way," Crosby said. "We did a pretty good job tonight, and there were some points in the third where they came pretty hard and especially when they made it 4-3 on that play by Killorn. So, we had to stay with it.
"We were tested, but overall we played a pretty good game."
Pittsburgh (24-9-5) passed Tampa Bay (24-12-4) in the Eastern Conference standings and ended the Lightning's four-game winning streak, which began with a 4-3 win against the Penguins on Dec. 23.
The Penguins jumped out to an early lead on Chris Kunitz's 12th goal, scored 1:56 into the first period.
With Anton Stralman in the penalty box for tripping Pittsburgh forward Bryan Rust, Kris Letang took a slap shot that deflected off Tampa Bay starting goalie Ben Bishop's arm and behind his left pad. Kunitz lunged at the free puck and poked it past the goal line.
Andrew Ebbett added to the lead with a goal, his first with the Penguins, on his birthday.
Ebbett received a stretch pass from defenseman Simon Despres before spinning and sliding a backhand pass to Evgeni Malkin. The goal horn sounded as a strobe light flashed over Bishop when Malkin's shot hit the left goal post. Ebbett corralled the rebound and scored on a backhand 6:50 into the first.
"We have to regroup after that," Lightning coach Jon Cooper said. "Ultimately, we end up over-backchecking to the guy wide open, a guy that can rope it, and he puts it in the back of the net, so we have to come back from that. The horn going off is irrelevant to the play. None of our guys stopped playing.
"Regardless of if that horn goes off, we still made dumb plays."
Malkin caused the goal horn to go off a second time in the opening period, scoring his 17th goal at 13:39 to make it 3-0. Despres took a slap shot that ricocheted off of Penguins forward Bryan Rust before Ebbett's rebound attempt bounced off Bishop's pad to Malkin, who scored on a wrist shot.
Bishop was pulled after allowing three goals on 10 shots.
Tampa Bay cut its deficit to two before the first period ended. Brian Boyle battled in the crease to gain possession of the puck before getting a wrist shot behind Greiss with 4:49 left in the first.
The Lightning cut the Penguins lead to 3-2 when Hedman scored an unusual goal with 7:12 remaining in the second period.
Hedman fanned on a rebound attempt off a Tyler Johnson wrist shot and chased the puck into the left corner. He flung the puck back at the Penguins crease and into Greiss' glove, but Greiss mishandled the shot and gloved it into the Pittsburgh net.
Pittsburgh re-established its two-goal lead when Christian Ehrhoff scored his third goal, each of which has been a game-winner, with 2:53 left in the second. Beau Bennett fed Ehrhoff a pass from the corner, and Ehrhoff sent a slap shot past Boyle and under Nabokov's glove for a 4-2 lead.
The Penguins ended a streak of three consecutive games with two goals or fewer. Crosby and Malkin, who had two points, were separated after playing the past few games together. Penguins coach Mike Johnston thought the lineup change contributed to their offensive outburst.
"Recognizing sort of where we were heading with the [David Perron] trade, and I think everybody knows, ideally we would like to have those three centers [Crosby, Malkin and Brandon Sutter]," Johnston said. "So, I thought the other night, they were OK together. I really like them 4-on-4, but I thought where we're heading today and tomorrow is to try to get back to three centers.
"That's our strength and we have to play to our strength."