The fading Flyers missed a chance to move into first-place tie in the Metropolitan Division on Wednesday night.
They dropped a 5-2 decision to Pittsburgh at the Wells Fargo Center and slipped three points behind the Penguins, who climbed atop the Metro, one point ahead of idle Washington.
"They're a very fast team and have a lot of skill, and that's a tough combination," defenseman Andrew MacDonald said.
The Flyers are in third place with 15 regular-season games remaining. They are just three points ahead of New Jersey, the wild-card leader.
It was the fourth straight loss for the Flyers, who had a 12-game points streak (10-0-2) before their current skid.
Conor Sheary scored a pair of goals and Sidney Crosby had three assists to pace Pittsburgh, which has won all three meetings against the Flyers this season, scoring five goals in each victory.
Trailing 2-1, Pittsburgh scored the last three goals of the second period, including two by Sheary, to build a 4-2 lead.
With the Flyers on a power play, Jordan Weal appeared to have an open net in front, but the puck bounced over his stick and the Penguins went down the other end and eventually made it 4-2 as Sheary scored on a rebound with 39.3 seconds left in the second period.
The Flyers' power play was 0 for 5 — and had just four shots — and is 1 for 19 in the last six games.
"It's one of those things where we need one bounce, need one to go in for us and then we get our confidence," said Travis Konecny, whose team will try to rebound Thursday against the powerful Bruins in Boston.
"They just pressured us a lot," Wayne Simmonds said about the Penguins' penalty-killing unit. "We have to find ways to get pucks to the middle of the ice to alleviate the pressure. We got the puck on the wall and they did a good job of not allowing us to get off."
Evgeni Malkin closed the scoring with an empty-net goal.
After playing an undisciplined first period, the Flyers swarmed Penguins rookie goalie Tristan Jarry early in the second stanza and took a 2-1 lead on goals by Jake Voracek (15th) and Konecny (18th).
Konecny, battling at the left side of the net, kept pounding away and scored on his second rebound attempt, putting the Flyers ahead, 2-1, with 14:59 remaining in the second.
"We got those two goals and were buzzing pretty good and got some real good opportunities…and then for whatever reason, we kind of backed off a little bit," MacDonald said.
A short time after the Flyers took a 2-1 lead, Eagles center/Mummer-for-life Jason Kelce was shown on the scoreboard leading a "Let's Go Flyers!" chant.
Instead, the slick-passing Penguins — now 14-6-2 in their last 22 games in Philadelphia — responded by scoring three goals in a 9:56 span.
"They took advantage of the opportunities they got," MacDonald said. "An odd-man rush, and they got pucks to the net and our coverage was a little soft on a few occasions."
With 10:36 left in the second, Penguins defenseman Jamie Oleksiak tied it with a point drive that appeared to deflect off MacDonald and past screened goalie Petr Mrazek. The Flyers challenged, claiming goaltender interference, but the goal stood.
Late in the period, the Flyers made a bad defensive pinch and it led to a two-on-one for Crosby and Sheary. Sheary, who was goal-less in his previous 15 games, scored on the rebound and the speedy Penguins had a 3-2 lead with 5:35 left in the second. He later made it 4-2.
Earlier, the Flyers couldn't get into a first-period offensive rhythm because they were too busy trying to kill four penalties in the opening 20 minutes.
Giving the NHL's best power play so many chances was a recipe for disaster. And on the Penguins' fourth power play of the first period, they finally connected. Malkin slid a goal-mouth pass through the legs of defenseman Radko Gudas, and Phil Kessel rammed in his 28th goal of the season, giving Pittsburgh a 1-0 lead with 1:25 to go in the first.
The goal was scored while Oskar Lindblom was in the penalty box for high sticking.
The Flyers had little attack time in the opening period, and they were sloppy on two abbreviated power plays. Their best scoring chance occurred when the teams were at even strength, but Brandon Manning, who was alone in front, deflected Claude Giroux's slick pass wide of Jarry.
Jarry's counterpart, Mrazek, has allowed 18 goals over his last four games. He surrendered a total of four goals in his first three games with the Flyers.
Three of the Penguins' goals were scored by Crosby's line against a unit centered by Val Filppula.