Doubt's clutches first gripped Adam Cianciarulo at 17.
He had been unbeatable and invincible to that point, knowing he could beat the other riders every time he pulled his dirt bike into the gate.
Cianciarulo shrugged off a shoulder injury as part of being a motocross racer. Breaking his leg the second day back on the bike had him wondering why me.
A crash in his first race back from the leg injury had him thinking, while still in the air, he might die on the concrete below. A third shoulder injury, on the left this time, crushed nearly all the confidence he had left.
Doubt, it appeared would not let go.
"I used to line up in the gate, look to my left, look to my right and think, I've got these guys beat, I've got them covered," Cianciarulo said. "Coming back from all those injuries, I started looking left and right and thinking, I don't have these guys. As an athlete, you become vulnerable, that feeling of maybe I was never really that good."
Through his own determination and a little help along the way, Cianciarulo rediscovered his confidence during a 250cc class championship run this summer. On Saturday night, he will make his 450cc debut at the Monster Energy Cup in Las Vegas.
A rut-filled path paved the way.
Cianciarulo's interest in motocross began on TV. He started watching races from his home in Claremont, Florida, at 3 and became enamored with Jeremy McGrath, toting a VHS tape of the seven-time champion's 1999 Supercross season everywhere he went.
On a dirt bike, young Adam was unrivaled, winning at every level. He signed with Kawasaki at 7 and his first pro contract with Pro Circuit Racing at 14. He finished his amateur career with a record 11 mini-bike national championships.
Cianciarulo was pegged as the next two-wheel star, in line behind McGrath, Ricky Carmichael, Ryan Villopoto, Ryan Dungey - maybe even surpassing them.
He lived up to the billing early in his first Supercross season, winning his 250cc debut and two other races in 2014.
"He made it look so easy," Pro Circuit Racing owner Mitch Payton said. "Every class he would elevate to, he would continue to win."
Cianciarulo's first taste of defeat came inside Toronto's Rogers Centre in 2014.
Holding a 17-point lead with three rounds left, he hit a section of whoops and injured his right shoulder while trying to hold onto the bike. He tried to race later that night, but the shoulder again popped out and the joint was too loose to continue.
Surgery for a torn rotator cuff and labrum followed, but through intense rehab, he was ready to ride again four months later.
Two days into his return, he suffered compound tibia and fibula fractures.
"That's when I was like, man, what's going on here?" he said.
The injury ride was just getting out of the gate.
For his first race back from the broken leg, Cianciarulo went to Geneva for an exhibition race, shortly after turning 18. Riding through a rhythm section, he lost control, sailed off the course and landed headfirst on the concrete.
"In the air, I was thinking: This might be it, I may die," he said. "That's the only time I've ever thought that on a dirt bike."
Cianciarulo remained unconscious for several minutes. He had to be strapped to a backboard and taken to a hospital.
Luckily, his head injury was not severe. His shoulder injury was.
Cianciarulo shattered the socket of his surgically repaired right shoulder, and re-tore the labrum and rotator cuff.
Three successive injuries sent Cianciarulo into a dark place. He remained the happy-go-lucky kid on the outside, but it was a facade to mask the anguish building inside.
A third shoulder injury - on the left - six races into his latest return caused Cianciarulo to question himself and his place in the sport.
"I was basically a bust. That's what I considered myself," he said. "I was always hurt, I could never stay on the track and the more I sat on my couch, the better everyone else was getting."
More injuries followed: a broken wrist in 2016, ACL reconstruction in 2018.
Though undeniably skilled, the tall, lanky rider could not seem to accomplish the single most important aspect of motocross racing: staying on the bike.
Skepticism about Cianciarulo's career spread through the industry, but Payton stuck by his young, talented rider, allowing him fight through the injuries, build back his confidence.
"If I scouted him and thought this kid's good, I'm not going to turn my back on him because I know my eyes didn't see something that wasn't there yet," Payton said. "They saw brilliance."
Teaming up with another underdog also helped Cianciarulo turn the corner.
Nick Wey was a fan favorite during an 18-year racing career, becoming beloved by overachieving as a privateer when he wasn't riding for factory teams.
Wey got to know Adam and his father through the years, appreciating the young rider's tenacity. When Alan Cianciarulo asked Wey to help coach his son, he started with a few pointers, became his full-time coach and this year became his trainer, too.
Tapping into Adam's desire to finally reach his potential, Wey worked on fine-tuning his riding while trying to rebuild his torn-down psyche.
"I think his lack of confidence as a professional after some early success was maybe partially due to not a total confidence in his preparation," Wey said. "Ultimately, he was making the same mistakes and over."
The work with Wey enhanced Cianciarulo's conviction to rebuild his career.
Even a setback would not derail his climb.
The 2019 Supercross championship all but in hand, Cianciarulo crashed out of the final race in Las Vegas, ending his title bid. Doubt briefly crept into his thoughts again. This time, he had the wherewithal to push it away.
Cianciarulo responded with one of the most consistent 250cc seasons in motocross history, winning six times, climbing the podium in all 12 races. A first professional championship in hand, a wave of elation, relief and appreciation washed over him.
"It's just given me a different perspective in life," said Cianciarulo, who turns 23 on Sunday. "Everything I went through was difficult, but I wouldn't trade it for the world because I feel like it's set me up for where I am now."
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