(CNN) Typically, when an athlete goes on to become a legend, their legacy can be traced back to a single breakthrough moment. A time in which they first tasted greatness, broke through and made a name for themselves and then, from that point on, never looked back.

But for the three-time defending CrossFit Games Champion Mat Fraser, the moment his career went from good to great was not as a result of a win, but rather an agonizing loss.

"For a long time I hated that [silver] medal," the 29-year-old American told CNN back in January in Miami. "It kept me up at night. It was a source of disappointment. Now I wouldn't trade that medal for anything."

As soon as the former weightlifter Fraser appeared on the CrossFit scene in 2014, he was immediately heralded as the future of the sport.

In his debut appearance at the CrossFit Games that very same year, Fraser finished runner-up behind the 4-time champion Rich Froning, who was stepping away from individual competitions, leaving the coast clear for Fraser to take up his mantle.

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But it wasn't that simple.

The following year, Fraser entered the event as the favorite but once again finished second, this time to Ben Smith.

Two silver medals, but each eliciting an entirely different reaction. While his silver medal in 2014 was met with a sense of achievement, his second silver changed everything.

"I hated my 2015 medal. To me it just represented the cut corners, the slacking off, the thinking I could out-train a bad diet," Fraser continued, "If I had won in 2015 while carrying those bad habits, I would've kept those bad habits. I would've thought I could do this while eating terribly. I can do this while training sporadically."

Instead, the future Fittest Man on Earth changed his entire routine.

He altered the way he trained and became more focused and disciplined in the process. Fraser also changed his diet. Or more accurately, he outsourced his entire caloric intake to his girlfriend, and now fiancee, Sammy Moniz, who documents their meals on her Instagram account 'Feeding the Frasers.'

After the 2016 CrossFit Games, where Fraser finally claimed his first gold, he and Sammy moved to Cookeville, Tennessee, home to the man who had beaten him the first time Fraser climbed the podium at the CrossFit Games, the four-time champion Froning.

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All these lifestyle changes worked, perhaps even better than he had imagined. Since that life-changing loss at the 2015 Games, Fraser has not lost a single competition at any level. Claiming three consecutive Gold medals at the CrossFit Games, each year by a greater margin of victory than the last.

But now Fraser faces a different problem. He has become so dominant in the sport, that fans of the sport no longer give him credit for his victories, suggesting instead that all he has to do to win is simply show up.

But Fraser believes they're not seeing the whole picture. "I was getting those comments all the time, like: 'What are you worried about?'" Fraser explains. "I'm dedicating everything I have for the months prior and there's a real possibility that things won't go right."

"They don't see the behind the scenes of how much goes into it. How dedicated my day to day is. That my life revolves around it. Eating, sleeping, training, social life. Everything."

When the Games get underway on August 1, Fraser will be the overwhelming favorite to win a fourth straight CrossFit Games, equaling the mark set by his new neighbor Rich Froning. A feat unimaginable if not for that fateful loss back in 2015.