The Flyers, looking like they can’t wait for the season to end, continued their swoon Tuesday night at Capital One Arena.

Coming off a devastating defeat to worst-in-the NHL Buffalo on Sunday, they played with little emotion in the opening period, fell into an early 4-1 hole, and lost to the much more physical Washington Capitals, 6-1.

“We kind of got beat all over the ice in basically every category,” goalie Brian Elliott said, adding that the fact the Flyers didn’t add anyone at Monday’s trade deadline did not factor into Tuesday’s flat performance.

The Flyers have lost four of their last five games and they fell six points behind Boston, which has two games in hand, for the final playoff spot. They had an 11-4-3 record at the start of March. Since then, they have eight wins in their last 24 games (8-13-3), and it’s fair to wonder when they will give some prospects a look in the season’s last 14 games.

It marked the seventh time this season the Flyers had lost by at least five goals.

Since a 7-4 win in Washington on Feb. 7, the Flyers have lost their last four meetings with the Capitals.

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Washington, the East Division leader, went 3-for-3 on the power play and moved two points ahead of the Islanders, who have a game in hand.

“We need to show consistency. That’s on me,” coach Alain Vigneault said before the game. “... We can start that tonight. I believe we have a good team. I believe we have a playoff team. There’s still hockey to be played here.”

His team didn’t get the message. They seemed to still be dazed from their 5-3 loss to Buffalo, a game in which they took a 3-2 lead into the waning minutes.

The Caps scored three goals in a 6:49 span to turn a 1-1 tie into a 4-1 first-period lead. Two of the goals were on the power play.

The Flyers’ defense, which had shown some improvement in recent games, appeared lost in the opening 20 minutes. The Caps had time and space as they spent most of the first period in the Flyers’ end and had a 19-9 shots domination against a shaky Elliott.

“We didn’t play hard enough in front of our goaltender,” Vigneault said.

He didn’t want to use it as an excuse, but he mentioned the Flyers’ grueling schedule.

“I will say it was our sixth game in nine nights, and it’s a tremendous amount of hockey,” Vigneault said.

Washington played its eighth game in 13 nights.

The Flyers’ penalty kill has been one of their few bright spots lately, going 10-for-10 in the previous three games. But it was disorganized on Washington’s first two power plays of the night, and the Caps converted on both opportunities to build a 3-1 lead.

Tom Wilson put a point-blank, power-play shot under Elliott’s arm to give the Capitals a 2-1 lead with 8:28 left in the first. About five minutes later, an all-alone Nicklas Backstrom fired upstairs with Elliott sprawled on the ice, putting the Caps ahead, 3-1.

The Caps took advantage of penalties on Shayne Gostsbehere (elbowing) and Nic Aube-Kubel (interference).

With 1:39 left in the first, an unguarded Carl Hagelin made it 4-1 as he put a slot shot through the legs of Elliott as Travis Sanheim shoved Garnet Hathaway into the goaltender.

“Obviously, I didn’t like at all the way we came out,” Vigneault said. “That’s not the way you give yourself a chance against a strong opponent.”

Earlier, Sean Couturier had tied the score at 1-1 as he redirected James van Riemsdyk’s shot/pass past Ilya Samsonov, who had given away the puck to put the play in motion.

That offset Conor Sheary’s goal just 7:07 into the game. Elliott came out of the net and was out of position as Sheary (three points) scored from a sharp angle on the left.

Left winger Anthony Mantha, acquired from Detroit in a blockbuster trade Monday, made it 5-1 midway through the second period, scoring from the high slot and giving him two points on the night.

“I can’t ask for much better in my first game here,” said Mantha, who was on the Caps’ second line, with Backstrom and T.J. Oshie. “Hopefully we get our chemistry going over the next couple games and catch fire.”

Alex Ovechkin added a power-play goal from his office, the left circle, to increase the lead to 6-1 early in the third period. It was his 22nd goal this year, and the 728th of his amazing career, and it gave him six goals in five games against the Flyers this season.

Elliott, who had won four of his previous five starts, has struggled against the Capitals (28-11-4) this season. He had a 5.13 GAA and a .774 save percentage in two games against Washington before Tuesday.

Carter Hart will get the call Thursday in Pittsburgh (27-13-2).

Maybe the Flyers (19-17-6) will show up for that game.

Maybe.

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