The concept isn’t radical, nor is it unique to the Washington Capitals, yet there it was Sunday, in an improbable 5-4 overtime comeback thriller that will go down as one of the wildest wins in franchise history.

It’s a cliche, but it’s one that Coach Todd Reirden knows has been a major part of his team’s success. Players have preached it over and over through the Capitals’ 43 games this season, yet as the wins keep piling up, it’s getting harder to ignore: This team has no quit. Not after deflating mistakes. Not down two goals with a minute left.

Sunday’s victory against the Sharks — after rallying from two goals down in the final minute of regulation to force overtime — was the Capitals’ 14th comeback win, tied with the St. Louis Blues for the most in the NHL.

This Capitals squad is tightknit, that much is for certain. There are still 12 members from the 2018 Stanley Cup run, with the recent acquisitions having blended in as though they also raised the trophy. The dressing room has more moments of laughter and jokes than serious, hushed conversations. It’s a group that knows how to have fun: The players sprayed bottles of champagne as though they were celebrating their own victory when the Washington Nationals won the World Series, and they picked out their own goal songs for the season.

Even in the toughest situations, they believe that they can pull off the impossible. Some of it comes with the residual confidence of the Stanley Cup run. Another part comes with the experience of the group — backup goalie Ilya Samsonov is the only rookie. Whatever the case, the Capitals are leading the league, and their resilience is a major factor.

“Pretty veteran group in here, pretty close group, and when you have that, you tend to keep on working for each other,” T.J. Oshie said.

Sunday was just another example. The Capitals made plenty of mistakes that put them in a hole, but players made up for them in their own ways. Yes, they might have let the team down once, but given a second opportunity? Not so fast.

“I think that’s the one thing that our team has established,” Reirden said. “If you make a mistake, you’re going to get another opportunity to go out and make it right. And don’t rest on that: Respond. Respond. Not for yourself, but for the team. And your mistakes can’t drag down the rest of the group. I think that’s been the thing that I like about our resilience and non-quit attitude.”

One of the biggest examples was Lars Eller. The center scored the overtime goal past Sharks goaltender Martin Jones’s glove on a two-on-one break with just over three minutes left in three-on-three overtime Sunday. Before that, Eller had been on the ice for both of San Jose’s power-play goals by Evander Kane and was relatively quiet. But the coaching staff had the confidence to put him back on the ice when it needed him to produce, and he did.

Look a bit further: Eller’s winning goal was assisted by John Carlson and Braden Holtby. Both had mistakes to make up for as well. Carlson got caught in a bad position that led to San Jose’s empty-netter with 1:00 left in the game to put the Sharks up 4-2. After Jakub Vrana scored with 47 seconds left to cut the lead to one, Reirden had a decision to make: “Do you put John back out there or do you not?”

And as it has been all season, the answer was simple for Reirden: “Of course you put your guys out there that are leaders and guys that are your team’s top players. You put them on the ice to have the chance again, and then they do it.” Seconds later, Oshie scored the equalizer, sending the game into overtime. It was the team’s seventh six-on-five goal of the season, and all of the key leaders were on the ice.

Holtby struggled in his previous three starts and had given up three goals in Sunday’s game, but he was the wall Washington needed in overtime. Eller said he needed to come up with something “extraordinary” in the extra frame, and he did.

“I think that’s just kind of been my philosophy and always has been last year and this year and even prior times: You go back with your guys that earned the opportunity,” Reirden said. “That’s something like this, like Braden. He’s got a fair body of work, that’s for sure, in this league, and [with] his win numbers and being an all-star, he deserves that chance to go back in there today. And he ends up making deciding saves to help us win that extra point.”

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