Before switching to a Ghost Rider-themed mask late in training camp, the back of Carter Hart’s helmet was a tribute to AC/DC: “IN ROCK WE TRUST. IT’S ROCK OR BUST.”

Two years ago, in his first full NHL season, it was easy to trust Hart. He was very good in the regular season — sometimes dominant — and even better in the playoffs. At just 21 — he turned 22 during the pandemic-delayed playoffs — Hart posted a 24-13-3 record, a .914 save percentage, and a 2.42 goals-against average. He had just led the Flyers to within a game of the Eastern Conference finals, and his .926 save percentage during the playoffs was the best by a Flyers goalie since John Vanbiesbrouck in 1989-99 (minimum: five games started).

Stardom appeared imminent.

His 2021 season, of course, was a disaster. Statistically, no NHL goalie had a worse year.

So now the Flyers, Cup-less since 1975, have a major question as they prepare to open their season Friday against Vancouver: Which Carter Hart will show up?

The young phenom from two years ago, or the guy who looked lost last season?

“There’s obviously lessons for him to be learned from last year, but last year is behind us,” Flyers coach Alain Vigneault said early in training camp. “Let’s focus on the present. Let’s get to work, and that’s what Carter needs to do”

Work has never been an issue for the driven Hart.

“Carter’s looking good right now. He looks confident,” captain Claude Giroux said. “Mentally, he looks loose and ready to go.”

» READ MORE: Are new Flyers D-men Ryan Ellis, Rasmus Ristolainen, and Keith Yandle the solution to the team’s defensive woes?

Simply put: All the bold moves Flyers general manager Chuck Fletcher made in the offseason won’t mean much if Hart doesn’t rebound.

Fletcher knows it. Hart knows it. Hart’s teammates know it.

Oh, they dance around it when discussing this season. They talk about the new-look defense. They talk about allowing opponents fewer high-quality chances.

About last season ...

Hart (3.67 GAA, .877 save percentage) had the worst season of a Flyers goalie (minimum: 25 games) since Tommy Söderström in 1993-94. His save percentage ranked dead last among the 51 goalies who played at least 1,000 minutes last season.

Hart doesn’t like to talk about either his struggles or the team’s. Instead, he said he has “turned the page.”

”Last year was difficult for everybody,” Hart said on Sunday. “It was a weird year; a lot of different factors played into things, but at the end of the day, our group wasn’t as good as we could be. We know we’re a lot better, and that’s in the past. We’re focusing on this year, and we’re really excited to get things going. We have a fun group here.”

The Flyers finished last in the league in allowing 3.52 goals a game, but it wasn’t all on Hart. The forwards didn’t always play a 200-foot game, and the defense was porous.

“It’s always a team effort, but obviously it’s easy to point the finger at the goalie, the last line of defense,” left winger James van Riemsdyk said. “Ultimately what happened last year wasn’t a singular thing where it was just one piece. It was a lot of parts of our game that were not very consistent, and I think that showed up over the course of the season.”

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Van Riemsdyk said the Flyers “let in too many goals, but to just pinpoint that on goaltending would be unfair. Those guys always battled in there for us and gave us a chance. Ultimately, playing a little bit better and playing a little bit smarter in front of them is going to be what we need to do to get off to a good start.”

Kim Dillabaugh, the Flyers goalie coach, stayed in touch with Hart, and all his goaltenders, throughout the summer “to see where they’re at and how everything is going from an on-ice and off-ice perspective. Carter has spent a lot of time on both fronts. He’s got a great network of people he works with back in Edmonton.”

In the summer, Dillabaugh traveled to Edmonton to spend time with Hart, watching him and his personal goalie coach, Dustin Schwartz, “work and see where they are at,” he said before training camp. “He’s invested a lot of time like he normally does, and he’s obviously excited about getting around his teammates and getting the season going.”

Hart, 23, took some time off early in the summer to regroup.

“I needed a bit of a break after the season,” said Hart, who missed a scheduled preseason start Friday because of minor “bumps and bruises” but will be ready for the opener Friday, according to Vigneault. “Just took a little bit of time off the ice. Had to recharge the batteries a bit, so it was good. Got into tennis a little bit this summer and that was fun; it was good to recharge the batteries and then have a good summer of training, also.

“I just wanted to get bigger, stronger, and faster,” he added. “I feel good. Feel ready to go.”

Some of Hart’s struggles weren’t helped by the fact that COVID-19 caused him to be isolated from his teammates. The married players had company all the time. Hart, who is single, did not.

After last season, Hart admitted there were lonely times for him.

“You kind of go home and you’re just in your own thoughts the whole time because you just sit and sit in your apartment alone,” he said in May. “But things were a lot better at the end [of the season]. I was feeling a lot happier and hanging out with the boys more.”

Said Vigneault: “You have to go through adversity to get better and to grow. He’s gone through that … probably for the first time in his life and his career.”

Hart, selected by the Flyers in the second round (48th overall) of the 2016 draft, was impeccable playing for the Everett Silvertips in the Western Hockey League, becoming the first goalie to win the CHL Goaltender of the Year Award twice. He also backstopped Team Canada to the World Junior title in 2018, and built expectations as the NHL’s next great goaltender. That hype seemed on target after his first two years with the Flyers.

His struggles were totally unexpected. It was a year in which Hart was noticeably vulnerable on high shots to the glove side.

“Sometimes you have a drop-off in certain areas that you need to address and focus on,” Dillabaugh said. “That’s something we do on a daily basis.”

In the offseason, Hart worked on improving that vulnerable area in his game. He didn’t want to get into specifics.

“That’s just between my goalie coach and myself,” he said. “Those areas we’ve targeted, we’ve made some progress. I’m feeling really, really confident in those areas.

Hart is expected to play a bulk of this season, and a 52-30 split in games with new backup Martin Jones seems logical.

“If we have two goaltenders playing at a high level, the time kind of works itself out,” Dillabaugh said.

Jones, 31, will serve the mentor role for Hart that was formerly held by Brian Elliott.

“Our goal is to push each other and try to learn from each other,” Jones said. “I love watching him play, and it’s going to be fun to sort of get a front-row view and be able to work with him.”

Perhaps Hart felt pressure last season because a new contract was hanging over his head. In August, Hart signed a three-year deal that totals $11.94 million, an annual $3.98 million salary-cap hit.

“Chuck and his group have shown a tremendous amount of confidence with the contract they gave him this summer,” Vigneault said. “I believe in Carter. Our coaching staff believes in Carter.”

“Everybody likes to have security and likes to have those things taken care of so their focus can stay solely on the game and play at a high level,” Dillabaugh said. “That’s one less thing that can take your focus away.”

Fletcher is perhaps Hart’s biggest supporter.

“He’s a top-end talent,” the GM said after last season. “It’s a tough league, but he’ll make the adjustments and he’ll return to form.”

Signing the contract, Hart said, “It was nice to get that done. Now I can just go play.”

Hart isn’t the only goalie, of course, to have a poor season early in his career. Countless goaltenders overcame a scuffling season before they blossomed into stars.

That realization should ease Hart’s burden. So should the fact that the Flyers added three veteran defensemen — Ryan Ellis, Rasmus Ristolainen, and Keith Yandle — to decrease some of those Grade A scoring chances against them.

“They’re solid defenders and I’m looking forward to playing alongside them,” Hart said. “I mean, defensemen have to be the goalie’s best friends.”

In his two preseason appearances this year, Hart had a 1.20 GAA and a .953 save percentage. He looked more confident and challenged shooters more often. Assertive is the word Vigneault used to describe him.

“He’s fully in the present, which is where you need to be as a goaltender,” said Fletcher, noting that Hart is smiling more. “I imagine pitchers, quarterbacks, goaltenders, you don’t dwell” on the past. “You’ve got to be in the present. That’s where he’s at.”

After finishing as the East’s top seed two years ago (after the qualifying round), the Flyers failed to make last season’s playoffs.

“We all had to reset,” Fletcher said. “... It was a tough year. I had a bad year. I don’t think that’s the best year our coaching staff has ever had. It certainly wasn’t the best year most of our players had. We owned it collectively.”

That includes Hart, a still-blossoming player who, when he’s on his game, has the ability to carry the Flyers further than any player on the team. Will it happen this season? Next season? Down the road?

For Hart, who has the ability to be the best homegrown goalie in franchise history, the possibilities are endless.