When Rey Mysterio forced Randy Orton's shoulders down for the three-count at WrestleMania, he completed the final chapter of a storybook ending to one of the most unlikely underdog tales in WWE history. At 5 foot 6, Rey Mysterio is one of the smallest competitors to ever grace a WWE ring. But what he may lack in size, he has made up for in heart, never giving up on his road to the World Heavyweight Championship. Because of his shorter stature, that road to the top was never easy for Mysterio.

Growing up in Tijuana, Mexico, Rey was no stranger to the ring. His uncle, the original Rey Mysterio, was a star in Mexico and exposed Rey to the business at a young age. As Rey explains, "From Day One, my mind was set on one thing -- being a professional wrestler. I watched wrestling tapes, trained with my uncle, and with some of the best wrestlers in Mexico."

At just 15 years old, Rey thought he was finally ready to wrestle in front of an audience. However, his age proved to be obstacle -- the first of many roadblocks Mysterio would encounter on his road to the top. "In Mexico, to become a pro wrestler you have to have a wrestling license, and to get a license, you have to pass a wrestling test," explains Mysterio. The problem for Rey was that to take the wrestling test, a person had to be at least 18 years old. Rey was three years underage, but decided to take the test anyway.

"After I passed the test, I got a call from the wrestling and boxing commission. They said there was a major problem. Since I was only 15, they couldn't just give me a wrestling license. So we worked out a deal where they would give me the license as long as my parents signed a waiver saying they claim all responsibility if anything happens to me in the ring." With his new license in hand, Rey started contacting wrestling promoters looking for work.

Over the next several years, Rey continued to train hard while wrestling in front of small audiences in Tijuana. It didn't take long before Rey started to get noticed. "When I was 17, I got a call from Konnan. He told me that he was about to start up a new promotion called AAA. A lot of the popular wrestlers were going to come to work for him, and he wanted me to be one of them," says Mysterio.

At first, the decision was difficult for Rey. AAA was based in Mexico City, so for Rey to join, he would have to leave his parents, girlfriend, and schooling behind. "I told Konnan I wasn't sure if I could do it. He said to me ‘Do you want to go to school for the rest of your life, or do you want to be a wrestler?'" For Rey, the decision suddenly became a lot less complicated. Rey packed his belongings, and headed to Mexico City.

When Rey got to Mexico, more adversity was there to greet him. "When I got to AAA, I was introduced to the company's promoter, Antonio Pena. The first thing he said was that because of my size, I would be working with the minis. In Mexico, the minis were the wrestlers that were bigger than midgets, but too small to wrestle with the heavyweights. But Konnan stuck up for me. He told Pena to give me a chance, and to watch me wrestle before he decided to put me with the minis."

Rey got his chance at AAA's inaugural TV taping. He stole the show in his very first match. "I was in the ring with Psicosis, Super Calo and Heavy Metal. During the match, I did a dive that was called the ‘Dive of the Month' and it really got people's attention. It was like a big shining star hit me. After the match, Antonio Pena told me he was impressed with my work. He said ‘You're pretty good kid, and you've got potential,'" remembers Rey.

From there, Rey's in-ring ability continued to help prove that he could hang with the big boys. But still, not everybody was a believer. In fact, according to Mysterio, there are still a number of skeptics out there today. "A lot of people have doubted me because of my size. They think someone like me doesn't deserve to be in the main event, but I think if they knew me, and knew what I've been through in my career, they would respect me. For me, the people who doubt me only fuel me to prove them wrong. I want to prove to them that I am better than they think I am, and that I deserve to be on top and I deserve to be World Heavyweight Champion."

With each passing week, Rey Mysterio continues to prove that he belongs in the ring with the bigger men and that he deserved to be World Heavyweight Champion. And as the number of detractors quickly start to fade, Rey knows that it was the people in the stands standing behind him since Day One that helped propel him to the top.

"My goal was always to go out there and entertain the fans," claims Mysterio. "I wouldn't be where I am today without my fans. I want to thank them for their support, and for believing in the underdog."