Leino scored twice in the third period for the Flyers, who rallied to beat the Penguins 5-2 on Tuesday night to stay atop the Eastern Conference.
Philadelphia has led the Eastern Conference and the Atlantic Division since Jan. 8, but the Penguins had won eight of 10 and had a chance to tie their cross-state rivals at 100 points with a regulation victory.
"It's sometimes tough when teams are not that close to you and you're clear for playoffs and you're in the number one spot," Leino said. "But now teams are close to us. This was a desperate game today, and we played good."
Goals by Jeff Carter, Scott Hartnell, and Claude Giroux and 25 saves by Sergei Bobrovsky helped preserve the conference lead for the Flyers, who won in regulation for the second time in seven games. They have a three-point lead on Washington in the race for the No. 1 seed in the East.
Alexei Kovalev and Tyler Kennedy scored for Pittsburgh, which had won four straight games in a shootout to stay in the division race despite being without star centers Sidney Crosby and Evgeni Malkin for most of the second half of the season.
The Flyers used a few tricky bounces to beat Fleury, who had allowed only two goals in three games and had won six of eight starts with a 1.68 goals-against average and one shutout.
"A couple times it just bounced low everywhere and ended up in the net," Fleury said. "It's tough, especially against a team like that where we are fighting for a spot."
Carter was credited with Philadelphia's first goal, his team-high 35th. It was determined that Braydon Coburn's wrist shot from along the right-wing boards 15:56 in was deflected lightly by Carter's stick before hitting the far post. It then bounced back off the back of Fleury's pad and went in.
That tied it at 1 after Kovalev scored his 16th goal of the season and second in 15 games with Pittsburgh with 7:38 left in the first.
Leino had the final two goals of the game, each on a peculiar deflection. He made it 4-2 early in the third when Hartnell's shot from the point bounced off Leino's upper body as he stood just to the left of Fleury -- and then, again, off the back of Fleury and into the net.
"We haven't had those lucky bounces -- maybe those fluke goals, I guess you could say," Hartnell said. "But I think we were overdue."
Leino's 19th of the season came 3:08 later. His shot from right of the crease climbed up Fleury and fluttered over the goal line before Pittsburgh defenseman Zbynek Michalek could swat it out.
"A couple of those [goals] are not ones that Marc-Andre has anything to do [with] and really can't be too concerned about," Pittsburgh coach Dan Bylsma said.
"He certainly was not an issue in the game. We let them off the hook. We turned the game into a little more freewheeling than we needed it to be."
The Flyers, who lost 2-1 in a shootout at home to the Penguins on Thursday, have won all three games in Pittsburgh. Philadelphia is 16-3-2 against divisional opponents.
The Flyers took the lead for good over the Penguins with two goals 47 seconds apart late in the second, a sequence that began about a minute after Kennedy and Chris Kunitz had some chances to score with Bobrovsky down and out of the net but could not convert.
Hartnell tied it with a power-play goal with 6:15 left. Giroux's wrist shot from the slot, his 25th of the season and fifth against the Penguins, gave the Flyers the lead at 14:42.
"It shows a lot to come back on the road," Philadelphia coach Peter Laviolette said. "To fight back a couple times and get the lead."
Philadelphia has a four-point lead -- and a game in hand -- on the Penguins, who have only five games remaining.
"I don't think that we play hockey to win the division," Pittsburgh center Maxime Talbot said. "We play hockey to win in the playoffs and to get ready for them."
The Flyers set a team record with their 25th road win. ... The seven goals in the game were three more than the total output for the Penguins and their opponents in their previous three games combined. ... The Flyers are 6-1-4 in their past 11. ... Bylsma said that injured C Dustin Jeffrey -- out the past three games with a knee injury -- had an MRI that revealed damage. The extent hasn't been determined. ... Penguins C Mark Letestu returned after missing five games because of an undisclosed upper body injury.