NEW YORK - Craig Berube says his team isn't tired. The Flyers' third-period play recently suggests otherwise.

The long grind that had them play the final 17 regular-season games - many against elite teams - over the last 30 days seems to have caught up with the Flyers. They have been flat and outskated in most third periods lately.

If they don't awaken, they will soon have several months to catch up on their rest.

Berube doesn't buy the theory that the Flyers are fatigued, or that it played a role in their disastrous third period Thursday in New York, where the Rangers pulled away from a 1-1 tie and won the playoff opener, 4-1.

The Flyers should have been energized for the final 20 minutes, knowing they somehow were thisclose to taking the early control of the series. In Madison Square Garden, no less.

They were badly outplayed in the first two periods, but backup goalie Ray Emery kept them in a 1-1 tie. They had a chance to steal a game and the home-ice advantage by playing just one very good period.

Instead, they had a meltdown. Undisciplined, the Flyers seemed to have a man in the penalty box for most of the third period. The Rangers outscored them, 3-0, and outshot them, 13-1, in the final 20 minutes.

The Flyers have been outscored, 17-5, in the third period of their last eight games. That would seem to indicate they are a tired team.

"I don't know if we don't have any energy, or we're just not focusing on what we need to do," said winger Scott Hartnell, whose line, with Claude Giroux and Jake Voracek, has combined for just one goal in five games against the Rangers this season. "We need to get back to having energy. . . . It's how you think as a group. It starts with our line to go hard on every shift instead of, 'OK, we had a couple good shifts, let's just sit back.' We need to keep going and go after these guys. You can't sit back."

Berube was asked if he thought the late collapse Thursday was because of fatigue.

"No I don't at all," he said. "Going into the third period - and I looked at the tape - I thought things were good until that penalty."

A double-minor to Jason Akeson led to a pair of Rangers power-play goals 47 seconds apart, snapping a 1-1 tie.

"We have to do a better job of killing the penalty," Berube said.

It's understandable why the Flyers were tired down the stretch. At one point, they swept Pittsburgh (twice), Chicago, Dallas, and St. Louis in a grueling eight-day stretch. But they should not be fatigued for The Real Season because they had some R&R before the playoffs. They had clinched third place and were able to rest some regulars in the regular-season finale last Sunday, then had four days before the playoffs started Thursday.

Yet, these were Berube's words after the 4-1 Game 1 loss to the much more energetic Rangers: "I didn't think we had our legs. I didn't feel we skated well enough in any of the periods."

That sounds like a description of a worn-out team, one that has had to huff and puff ever since it started the season 1-7 and faced a long, uphill battle.

"We're going to skate better next game," Berube promised.

If they don't, they will be in a 2-0 series hole. Impossible to overcome? Not for a team that has rebounded impressively from an awful start and shown it can beat the NHL's heavyweights.

But certainly a much more daunting task.

Inside the Flyers: Garden of Evil

Madison Square Garden has been a house of horrors for the Flyers since their last win there in 2011. The numbers since then:

W      L      GF      GA

0       9       10       35