Aaron Pico shares how his family has helped him blossom into Bellator's top prospect ahead of his professional debut at Madison Square Garden. (1:37)

Editor's note: This story was originally published ahead of Aaron Pico's MMA debut in 2017.

Three years ago, Bellator MMA president Scott Coker took a call from longtime mixed martial arts manager Bob Cook -- who cut right to the chase.

"I've got him," Cook said. "I've got the next kid."

It was a statement Coker knew he shouldn't take lightly. Cook has a history of bringing untapped talent to Coker's doorstep, including a completely inexperienced heavyweight named Daniel Cormier in 2009, when Coker was CEO of the now-defunct promotion Strikeforce.

"Who is it?" Coker asked.

"His name is Aaron Pico," Cook said. "He's 17 years old."

Coker blinked. "Come on, Bob. He's 17?"

"No, Scott, I'm telling you," Cook said. "The kid lives in Los Angeles. He's a wrestler and a Golden Gloves boxer. You need to sign him now."

Over the next several months, the two sides would hash out a "developmental" contract, which Pico signed in November 2014, two months after his 18th birthday.

Terms of the deal have not been disclosed, but it provided Pico a monthly stipend and the freedom to make a run at the 2016 U.S. Olympic wrestling team. That run came to an end at the Olympic Trials, when Pico, 20, lost to Frank Molinaro in the finals by a point. Molinaro, by the way, was 27.

On Saturday, Pico will make his long-awaited professional MMA debut at Bellator: NYC in Madison Square Garden. By that time, it will have been 31 months since he officially signed with the promotion.

The unique business arrangement definitely turned heads in the sport, and it might have helped change it. Shortly after the deal was signed, then-UFC owner Lorenzo Fertitta got in touch with Cook to lodge a complaint.

"Lorenzo said, 'Hey, you didn't give us a shot at signing Pico,'" Cook recalled. "I said, 'Well, you guys don't have a program over there for someone with no fights.' He told me, 'Next time, give us a call.'

"The UFC has a developmental program now."

So Bellator has been writing Pico checks since 2014, even though he never intended to step into a cage during the first two years of the deal; his pro debut will take place in one of the most famous arenas in sports history, on pay-per-view; and the UFC's former owner was so irritated at missing out on the prized prospect that he personally called Pico's management team to make sure it didn't happen again.

Why? What is so special about Aaron Pico?

"I've been around a lot of great prospects," Cook says. "I was with B.J. Penn during his first pro fights. Cain Velasquez, Cormier. These guys have something in them. They're going to win, even with no experience.

"But I've never had someone at this high of a level who is so young."

Coker, who has promoted fights for more than 20 years, put it this way: "From everything I've seen and heard, Aaron Pico may be the greatest prospect in the history of MMA."

Aaron Pico spars with his longtime boxing coach Dominic Viloria at the legendary Wild Card Boxing Club in Hollywood. Melissa Lyttle for ESPN

Dominic Viloria moved to Whittier, California, just south of Los Angeles, in 2000. At that time, he was regularly competing in professional Muay Thai.

His day job was constructing custom swimming pools, but he always loved combat sports. He frequently worked out in a gym he'd assembled inside his garage, usually with the door open to circulate air.

That's where he met his 4-year-old next door neighbor, Aaron Pico.

"He would come over and watch me hit the bag and say, 'Why do you train so hard, Dominic?" Viloria recalls. "I'd tell him, 'Because the other guy could always be training just as hard.'"

When Viloria would turn back to the bag, Pico would crouch on all fours and fire off pushups. Occasionally, he wouldn't leave, even after Viloria finished working out and headed inside. Viloria said he remembers eating breakfast at his kitchen table and Pico suddenly appearing in the chair next to him.

"I don't know why I did that," Pico said, laughing. "I would just walk into his house and try to hang out with him."

Pico started wrestling at 4, and by the time he was 6, he was doing so in national tournaments. It was clear he had a gift. His brother, Patrick, older by four years, was wrestling as well, and Pico would jump on the mats with the older kids. He'd do very well.

Soon, tournaments weren't enough. Pico's father, Anthony, met other dads on the road and would arrange "scraps." Pico and a couple of other local kids -- they called themselves "Monster Garage" -- would fly to Oklahoma for the weekend. And then Oregon. Or they'd invite top wrestlers to California.

At these gatherings, Pico would often go against heavier, older kids, the ones he couldn't wrestle in official competitions.

"We'd just fly there, lock the door and wrestle for a few hours," Anthony said. "When it got ugly, that's when Aaron would have the most fun. Most kids, you see their eyes swell up. 'I don't want to be here.' They're rattled.

"Aaron would turn around with a smile and say, 'Let's get a Slurpee and do this again tomorrow.'"

Pico's love for the scrap started to dictate his every move. He was training heavily in boxing by age 9. When he turned 12, he flew to Japan by himself and stayed a full month, sparring with a female fighter who'd turned pro. A couple of years later, he won a junior Golden Gloves tournament in Nevada.

There were MMA fights, too, which Pico admits were "kind of illegal." Viloria, who remains Pico's boxing coach to this day, remembers a cage fight on an Indian reservation around 2009 in which Pico lifted a kid over his shoulders and slammed him in front of a raucous crowd.

At 13, Pico entered the European Pankration Championships, a tournament in Ukraine much like MMA except with no blows to the head. It was there that his life took a major turn -- before flying overseas, Pico enlisted Ukrainian wrestling master Valentin Kalika as a coach and interpreter.

In the coming years, Kalika would end up becoming more like a second father.

Aaron Pico, left, and former UFC bantamweight champion TJ Dillashaw, right, work out with medicine balls during an intense morning of circuit training with their strength and conditioning coach. Melissa Lyttle for ESPN

If you ever want to make Pico's head spin, ask him to list every country he has ever been to.

"Oh, man," Pico begins. "Japan, Israel, Ukraine. All over Russia. Siberia, Bulgaria, Italy, Cuba, Uzbekistan."

His father, sitting nearby, chimes in: "Germany, France, Monaco, Mexico, Turkey, Croatia, Peru."

It's not unusual for a world-class wrestler to travel the globe, but Pico is, once again, an unusual case.

As a high school freshman at St. John's Bosco in 2013, he went 42-0 and won a California state championship. At that time, talks about his future naturally centered around three more state titles, with an eye on the NCAA collegiate level.

Chael Sonnen on Aaron Pico... "This is the No. 1 prospect in the history of MMA. I have never seen a guy come in more coveted, more praise around him, more pressure put on him and more anticipation than Aaron Pico. I truly believe not only will he take over the division, he will become the face of the company and the face of the industry."

But Kalika, who continued to coach Pico after their experience at the Pankration championships in Ukraine, had bigger ideas.

"I told him, 'If you want to be a state champion in California, you don't need a personal coach. You're a tough kid, and you'll have no trouble winning. But if you want to be an Olympic champ, I'll coach you, for free, twice a day, whatever it takes. But I want to make sure you're committed to winning an Olympics,'" Kalika said.

Part of that commitment was year-round international competition, which Kalika wanted Pico to start immediately. So before what would have been his sophomore year in high school, Pico withdrew. He'd earn his degree online, but he'd never step foot in a classroom again. The majority of the next two years of his life was spent abroad, always with Kalika at his side.

All expenses were paid by supporters of U.S. wrestling. Pico was an obvious investment. The kid had potentially three Olympic cycles in him: 2016, 2020 and 2024.

"It was a ballsy decision," former U.S. Olympian and NCAA national champion Ben Askren says. "I've never seen anyone else do that. A lot of people were interested to see how that experiment would work."

Says Pico: "It honestly felt normal to me. People said that high school and college were the 'safe route,' but that never felt safe to me. I wanted to wrestle, then go into fighting and become a world champion. Going to school -- that's time I could be using to develop skills in my real profession. So to me, the route I took was the safe route."

If there were any drawbacks in the decision, they had nothing to do with missing out on a "normal" life. Looking back, Pico can think of only two: loneliness and a constant fear his boxing technique was falling behind because all of his time and energy went into wrestling.

He dealt with both of those negative aspects the same way.

"I watched so many boxing videos," Pico said. "Overseas, after a tournament, I'd walk to a coffee shop by myself and just watch boxing videos for literally hours. I think that's why I came back and picked it up again so fast. To be honest, any time I'd get sad or homesick, I would turn on boxing, and that would just all go away."

If Pico does attempt to make the Olympics in 2020, he'd have to put his fighting career on hold again, possibly as early as next year.

Kalika, who served as a U.S. Olympic women's coach in 2016, doesn't mind saying he hopes Pico will return to the mats. But with his MMA career set to take off, that's obviously no guarantee.

"Inside of my heart, I hope he wrestles again," Kalika said. "He tried to make the Olympics as a 20-year-old and almost did, but that would have been rare. I deeply believe that in 2020, making the team would not be an issue. I'm pretty sure he would dominate. From 2018 to 2020, he would be a monster.

"But I know he loves to fight."

Aaron Pico takes a 30-second breather while training at the legendary Wild Card Boxing Club in Hollywood. Melissa Lyttle for ESPN

Pico is still living out of a suitcase this summer, although he's not boarding many airplanes. These days, his mode of transportation is a Mercedes Sprinter 2500 Touring Coach, a fancy name for what is, more simply, a freaking enormous van, complete with a shower, bathroom and kitchenette.

Armed with a carry-on suitcase holding fresh clothes, Pico bounces around Southern California traffic in this daily. It's driven by Anthony, who retired several weeks ago from his longtime job in medical equipment sales. Overseeing the start of his 20-year-old son's MMA career has become a full-time job.

Pico hones his striking in one of the world's most famous gyms: Freddie Roach's Wild Card Boxing in Hollywood. If need be, he has the privilege of utilizing the private area, in the same ring Roach trains his most famous pupil, eight-division world champion Manny Pacquiao.

His nutrition and strength and conditioning are handled by Sam Calavitta, a longtime high school calculus teacher and triathlete, who has compiled thousands of metrics on Pico's vitals in the past two months. Calavitta is known for having the most scientific, data-driven approach to performance advancement in the sport.

"When I first started working with him, he didn't just ask what my diet consisted of," Pico said. "He asked what deodorant and toothpaste I was using."

Pico's Brazilian Jiu-Jitsu is overseen by Eddie Bravo, one of the most well-known and established figures in grappling. The two linked up through a mutual acquaintance, UFC commentator Joe Rogan.

"Joe hit me up and said there's this badass wrestler that wanted to train with me," Bravo said. "I don't really follow the wrestling world, so I had no idea who he was. I looked him up on YouTube a few weeks after he started and told him, 'Holy s---, dude. I had no idea.'

"If he stays in our system, he will be looked at as one of the best submission artists in the game. What he brings -- the athleticism and wrestling -- I know what that translates into with the stuff I can show him."

It all culminates Saturday, when Pico will finally enter the professional cage for the first time. He'll do so against Zach Freeman, a 33-year-old from St. Charles, Missouri, who will surely be motivated to derail the hype.

LeBron James was a high school junior when he was first featured on the cover of Sports Illustrated in 2002. Bryce Harper was 16 when he landed the same cover in 2009.

Is Pico MMA's equivalent? Is he the greatest prospect of all time? And was he really worth a Bellator investment at age 18?

Asked to answer the question himself, Pico doesn't hesitate.

"I feel confident saying I'm the best prospect of all time, because of the work I've put in," Pico says. "There's nobody in the world who can spar at Wild Card, then go wrestle at the highest level right after.

"Come live one day with me, and let's see if you can hang. This isn't new to me. This is how I've been living my entire life, since I was 7 years old. I invite anybody to come try."