Alex Ovechkin celebrates his third goal of the game during the third period of the Capitals’ shootout win on Thursday night. (Adrian Wyld/AP)

For all the talk of how much had changed with the Washington Capitals, Alex Ovechkin showed what has remained the same in the third period at Canadian Tire Centre on Thursday night. With the Capitals facing an opening-night loss to the Ottawa Senators, debuting a lineup that was pieced together after offseason roster upheaval, Ovechkin flashed his best form even as his team struggled to find its.

He scored three goals in less than seven minutes to tie the game, his 18th career hat trick and the first to come on opening night. His effort pushed the game to a shootout, where he found the net again along with teammate Evgeny Kuznetsov to lift the Capitals to a 5-4 win.

“It’s nice to get a hatty, but the most important thing mentally wise, we need the win,” Ovechkin said. “We got it.”

Washington’s players, coaches and executives have acknowledged that the team isn’t as strong on paper as it was a year ago. This Capitals team has flaws, and the offseason departures of Justin Williams and Marcus Johansson left Washington with a lot of goal production to replace. That burden falls largely on Ovechkin, who is coming off a down year with 33 goals and just 16 at even strength, a career low for him.

Before the game, 21-year-old Jakub Vrana told Ovechkin he had a feeling. He told Ovechkin that if he notched two goals in the game, he might as well score a third. When the third period arrived, Ovechkin scored from his spot in the left faceoff circle. He scored down low in a tic-tac-toe passing sequence with Vrana and Kuznetsov.

“I came to him, like, ‘You remember what I said?’ Next shift — goal,” Vrana said.

Some hats littered the ice even though Ovechkin was the enemy. Washington looked like a team that has kinks to work through this season, but Ovechkin looked like his old self. He isn’t usually in the top three of the Capitals’ shootout rotation, but Coach Barry Trotz decided to ride the hot hands and deployed him second, after T.J. Oshie. Ovechkin scored again.

“When he’s excited and demanding the puck and loves scoring the goals, he’s an animal out there,” defenseman Matt Niskanen said.

“I could see them talking, Kuzy and [Ovechkin], they just sort of said, ‘Hey, we’ve got to do something here,’ ” Trotz said.

The Capitals sleepwalked through the preseason, and Trotz acknowledged the team was still in a haze after another dazzling regular season ended in a second-round playoff loss to the Pittsburgh Penguins last spring. Through the first six exhibition games, Washington had scored eight goals with just three at five-on-five, and Trotz lamented how his top players, including Ovechkin, weren’t producing. He also said that he trusted that would change when the games started to count.

It wasn’t just the disappointing ending to last season hanging over the team. The Capitals had a difficult offseason where salary cap constraints caused the most roster turnover in the past three years under Trotz. Kuznetsov, Oshie and Dmitry Orlov got big pay raises. But the team had to part with other players in favor of new, cheaper additions.

On Thursday night, the Capitals debuted an entirely new third pairing of Taylor Chorney and Aaron Ness, who played a combined 20 NHL games last season. Fourth-line center Jay Beagle skated with two new linemates, wingers Devante Smith-Pelly and Tyler Graovac, two of Washington’s unheralded summer additions. Vrana played in 21 games with the Capitals last season, he made the opening-night roster, impressing beside Ovechkin and Kuznetsov in the top-six forward corps.

Through two periods in Ottawa, that production from top players that Trotz has been wanting to see still had not yet arrived. After the teams combined for one shot on goal in the first six minutes of the game, an odd-angle shot by Chris Wideman at the half wall slipped past goaltender Braden Holtby to give the Senators a 1-0 lead just 6:25 into the game. But the Capitals tied it less than two minutes later on a snipe from Brett Connolly.

It appeared as though turnovers would doom the Capitals. Defenseman John Carlson’s pass in the neutral zone was picked off, and then forward Mark Stone got the puck in the slot, shooting it up and over Holtby. Two minutes into the third period, Niskanen had a defensive-zone turnover that lead to Derick Brassard’s goal and a 3-1 lead.

“I send a pizza right on the guy’s forehand and they make a play and score,” Niskanen said.

Ovechkin erased the two-goal deficit shortly after. Stone scored again to put Ottawa ahead one more time. Ovechkin tied it up again, carrying a team that’s going to need him this season. A win like this one, where the captain comes through in a big way, could be what jolts Washington to start.

“For whatever reason it was, we didn’t have a lot of enthusiasm in training camp,” Niskanen said. “Maybe a fun win like this where it’s a little bit higher scoring and we come from behind to tie it and win in a shootout, maybe it’ll spark a little bit and kind of get everybody excited to come back to the rink again.”