Now the question is whether the Flyers can rebound from a lost weekend that included a 6-3 loss to Tampa Bay on Saturday at the Wells Fargo Center. Next up is Tuesday's game at Buffalo.
Before this weekend, the Flyers were 10-2-1 in their previous 13 games.
The Flyers dropped to fourth place in the Metropolitan Division, one point behind the Rangers and Washington.
Former Flyers tough guy Dan Carcillo opened the scoring on an unassisted goal just 2 minutes, 14 seconds into the game. Carcillo came from behind the net and sent a backhander past Ray Emery.
Just 28 seconds later, Rick Nash knocked in a feed from Chris Kreider for his 11th goal of the season.
"We got off to that start and you don't give yourself a good chance," Emery said.
The Rangers made it 3-0 when Mats Zuccarello dug the puck out of the corner and fed an open Derick Brassard, who let a slapshot rip past Emery with 10:36 left in the first period.
The Rangers scored three goals on their first nine shots.
The Flyers trailed by 3-0 after the first period. It was the first time this year they allowed three goals in the opening period.
It wasn't as if the Flyers didn't have their chances. They outshot the Rangers, 17-13, but couldn't solve Henrik Lundqvist.
"The way we started the game helped everyone in here," Lundqvist said. "We got the crowd going and we got ourselves going."
The Flyers forced Lundqvist to make 37 saves, many of them spectacular.
"We like the way we played offensively and have our chances, but we need to do a better job in front," said captain Claude Giroux, who turned 26 on Sunday.
The Flyers played hard but were careless, allowing too many Rangers to skate freely into the offensive zone.
Still trailing 3-0, the Flyers were looking for a spark and thought they might have one when Luke Schenn engaged in a spirited fight with Carcillo.
Both got their licks in, but the momentum never changed.
Later in the second period, Kreider scored a power-play goal to make it 4-0 with 6:42 left.
At that point, the rout was officially on. Kreider skated in on goal uncontested and sent a shot that went off the skate of Flyers defenseman Braydon Coburn into the net.
That goal also snapped the Flyers' streak of success in 26 consecutive shorthanded situations.
The Flyers kept applying pressure in the third period and scored a power-play goal on Mark Streit's shot from the point with 13:11 left. Vincent Lecavalier recorded his 500th career assist on the goal.
The bad blood between the two teams was evident by late-game fisticuffs, including a bout between Brayden Schenn and the Rangers' John Moore with 11 seconds left.