ATLANTA >> For Marcus Mariota, the loss of confidence was the biggest blow.

He’d experienced so much success, from winning the Heisman Trophy to being the No. 2 pick in the NFL draft.

Then, for one of the rare times in his life, he wasn’t good enough.

“You go through a process of kind of looking within and reflecting,” Mariota remembered. “Throughout that journey for me, I kind of knew that I had to find my confidence to be able to play at a high level. When you get your confidence taken away from you, it’s tough as an athlete because I think that’s truly the only mental weapon you have.”

No journey of this type is ever complete, but Mariota feels he’s heading in the right direction again.

This past Sunday, he completed 13 of 14 passes, two of them for touchdowns, and ran for a score as the Atlanta Falcons surprised the San Francisco 49ers 28-14.

The Falcons (3-3), who were supposed to be in a massive rebuilding job, are surprisingly tied with Tampa Bay atop the NFC South.

And Mariota, who was supposed to merely mind the gap between longtime Falcons quarterback Matt Ryan and whatever prospect the team could land in next year’s draft, is showing flashes of the form that was supposed to carry him to NFL stardom.

He was even picked as the NFC offensive player of the week, an honor that was out of reach the past 2 1/2 years as he rode the bench for two teams.

Mariota knows how fortunate he is to even get a shot at starting again in the NFL.

“I’m forever grateful to this organization for allowing me to have that chance,” he said. “Across the league, a lot of guys in my situation don’t really get a second chance.”

Coming off a brilliant career at Oregon, Mariota was taken by the Tennessee Titans with the second pick of the 2015 draft. He was immediately handed the starting job and only heightened expectations by throwing four touchdown passes in his very first game.

Yet, even as he guided Tennessee to three straight winning seasons and a playoff victory during the 2017 campaign, his passing numbers were downright ordinary.

Mariota’s running ability gave the offense a bit of an extra weapon, but the grumbling among Titans fans only grew as their heralded quarterback was unable to push the team to the next level.

Then, during a dismal performance in Week 6 of the 2019 season, when he completed just 7 of 18 passes for 63 yards with two interceptions in a 16-0 loss at Denver, Titans coach Mike Vrabel decided he had seen enough.

Mariota was yanked. Ryan Tannehill took over, guiding Tennessee from a 2-4 start to a surprising run to the AFC championship game.

Mariota’s career as a Titan was over. He wouldn’t start another game in the NFL for 1,064 days.

“I felt like I was part of a good team, part of a good organization,” Mariota says now. “I thought if we could get the ball rolling, I could be there for a long time.”

Instead, he moved on to Las Vegas, where he spent two years backing up Derek Carr and getting scant playing time with the Raiders.

Just when it looked as if Mariota’s career might be on its last legs, he hooked up with his former offensive coordinator in Tennessee, Arthur Smith.

Heading into his second year as Atlanta’s coach, Smith needed a quarterback. The Falcons decided to trade longtime starter Ryan to ease their salary cap woes, and they didn’t have anyone ready to step into the job immediately.

Smith remembered Mariota’s potential and thought he could be just what his rebuilding team needed, at least in the short term.

Mariota got off to a rocky start, with four touchdown passes and four interceptions through his first five games, not to mention some major issues hanging on to the ball. He fumbled seven times, losing three of them.

Through it all, though, his steady demeanor was winning over his teammates. A quarterback’s job goes beyond the numbers. He also must be a leader, and Mariota fits that bill perfectly.

“That’s probably one of the coolest dudes I’ve ever met in my life,” safety Jaylinn Hawkins said. “He’s a very, very humble individual and sharp at what he does. He’s always poised. There’s no panic in his game. He has everybody’s back.”

Smith saw Mariota’s confidence growing with each start, especially when the Falcons won a couple of games and kept things close in their losses. The coach saw Mariota’s demeanor having an impact on those around him.

“These guys believe in him. Those are things you can’t put in a stat sheet,” Smith said. “He didn’t play for 2 1/2 years, so it took a couple of games. He was a little rusty here and there. But I feel like every game, he’s getting more comfortable.”

There’s still a long way to go in the season. If Mariota stumbles again, he could be one-and-done in Atlanta. If that happens, this could be his final chance to prove he’s capable of starting for an NFL team.

Mariota isn’t looking too far ahead.

After all, it took so long just to get back here.