ST. LOUIS — The energy at Enterprise Center was palpable as “Gloria” blasted through the speakers and a sea of St. Louis blue sang in unison before the puck was dropped Wednesday night. With their Stanley Cup banner getting raised into the arena’s rafters in a pregame ceremony, the Blues and their fans were buzzing as the season opener against the Washington Capitals got underway. For 60-plus minutes the energy pulsed as the game went to overtime knotted at two goals apiece.

Then, the building fell quiet.

The Blues fed off their home-ice electricity early, but the Capitals weathered the storm, rallied back from a two-goal first-period deficit and ultimately left with a 3-2 win when Jakub Vrana beat Jordan Binnington with a wrist shot with 2:09 left in overtime.

“We believed in ourselves and figured our game early enough to get it back,” Vrana said. “And [that is] the most important thing once you’re down like that early in the game. You have to keep on believing in your game, and that is what we did.”

The Blues had their chances in the third period but couldn’t solve Capitals goaltender Braden Holtby, who made 20 saves to keep the Blues at bay in a meeting of the past two Stanley Cup champions. Holtby wasn’t happy to give up the early goals but was pleased with how he and his teammates found their footing after the initial rush.

“Yeah, that’s not an ideal start to the season,” Holtby said with a sly smile. “I feel like I played the goals pretty well, I just misread bits of them to execute.”

The Capitals enter this season coming off a first-round playoff exit that left a sour taste in their mouths following the success of 2018.

That early loss led the team to break apart the group that sent a banner of its own into the rafters of Capital One Arena. New faces entered the room, with a revamped bottom-six forward group and young defensemen getting their shot. In goal, Holtby remains, but 22-year-old Ilya Samsonov won the backup role over incumbent Pheonix Copley. The core is intact — for now — and the Capitals want to take advantage.

“This is the start of a new journey, trying to get the Cup back,” said T.J. Oshie, who assisted on Vrana’s game-winner.

As the Capitals continue to work their way back to the top, the process will probably come in fits and starts. The opener showed the Capitals’ strengths and weaknesses.

Blues forward Sammy Blais scored 53 seconds into the game when the Capitals were caught scrambling in their own zone and Blais got to the front of the net for an easy tap-in off a silky pass from David Perron. The Blues found the back of the net again with captain Alex Pietrangelo’s one-timer from the left circle on the power play at the 7:55 mark of the first period.

“We knew they were going to come out really hard,” John Carlson said. “We could have played a lot better, but I don’t think we played terrible. They just had that little extra juice. . . . I just think we’ve been through these situations a lot and none of us thought we were out of the game.”

The Capitals cut their deficit in half less than eight minutes later when captain Alex Ovechkin blasted a shot from the right circle, beating Binnington. It was Ovechkin’s 11th goal in 15 career openers, which is the most among active players. Ovechkin said after the game that he felt he was getting a lot of scoring chances and felt “pretty good” on the ice.

It was the second period that proved to be the turning point for Washington. Holtby was a wall, keeping an explosive St. Louis offense off the score sheet. Defenseman Dmitry Orlov scored the equalizer from the right point on a power play at the 12:28 mark. After just one goal in his last 65 games of last season, Orlov’s tally marked just the second power-play goal of his eight-year career.

“The second period was a big swing period for us,” Coach Todd Reirden said. “. . . That’s what it’s really about, is everyone stepping up at different times, especially your core guys and your leaders.”

Orlov’s performance was part of a strong night for the Capitals’ blue line, including 19-year-old Martin Fehervary, who held his own in his NHL debut. Reirden praised the rookie, who was given the team’s “hard hat award” following the game for his efforts. The award is currently in the form of a Nationals hard-hat.

“He’s only 19 years old, so pretty special to watch that going on,” Reirden said.

Fehervary was slated to skate alongside Radko Gudas on the third pairing, but Reirden shuffled the defensive pairings early, moving Fehervary up and down. The group will continue to find its footing with lingering uncertainty about when defenseman Michal Kempny, who tore his hamstring in April, will be able to make his season debut. The team placed Kempny on its injured nonroster list Tuesday, but he was cleared for contact as of Wednesday morning.

And while the blue line will probably keep seeing movement as the team continues to mesh, the Capitals will get a look at another new face when they play the New York Islanders on Friday in what is expected to be Samsonov’s NHL debut.

“It was a good game for the season opener, and now we just need to pick it up and get better and better every game,” Orlov said.

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