On May 8, 2010 at the Bell Centre in Montreal, Canada, Mauricio “Shogun” Rua completed a journey years in the making.

Six years earlier, at the tender age of 22, Rua had taken the MMA world by storm, winning his first three fights in Pride before winning that promotion’s middleweight grand prix tournament in 2005. Entering the tournament as a heavy underdog, the Brazilian tore through then-superstar Rampage Jackson in the opening round and then won a unanimous decision against Antonio Rogerio Nogueira. Two months later, Rua scored a TKO finish against Alistair Overeem and capped it off with a knockout of Ricardo Arona to win the tournament. He was 23.

This dramatic series of wins led Sherdog to rank Shogun the #1 light heavyweight in the world. Which meant by the time Rua entered the UFC in 2007, he was riding a freight train of hype.

But hype doesn’t win fights, and Rua’s first UFC match was a disaster. Hampered by injuries, the No. 1 light heavyweight in the world gassed out early and succumbed to the relatively unheralded Forrest Griffin by rear-naked choke late in the third round. A few knee surgeries and a couple of victories later, however, Rua was given a title shot against the newly crowned light heavyweight champion, the unbeaten Lyoto “The Dragon” Machida.”

Unlike Rashad Evans, from whom Machida had taken the title a year earlier, Shogun was an experienced striker with an arsenal of kicks. That night at the Bell Centre, Rua used those kicks to punish Machida's legs over the five rounds. He would often initiate striking exchanges with punches, using them to set up his kicks.

Although Machida started out strong, Shogun's leg kicks wore him down. The fight was a five-round war and closely contested, but in the end Shogun seemed to have solved the riddle of the elusive counter-striking Machida, employing a game plan based around relentless offense, testing the limits of the karate master's footwork and durability. When the judges declared the reigning champion the winner, even Machida seemed surprised. Rua, meanwhile, was crushed. For his trouble he was awarded a win bonus from the UFC and an immediate rematch.

Just seven months later, at UFC 113, the two met again. Machida wore a different look on his face this time, perhaps anxious at the prospect of facing a man he now knew was able to injure him. The fight started with little feeling out. Shogun sought to continue his striking assault and Machida aimed to thwart it by taking the challenger down, which he did twice in the first three minutes.

With less than two minutes to go in the first round Machida landed one of his signature jumping knees to the body. Thinking he had Shogun stunned, Machida followed up with a straight left. Shogun dodged the punch and countered with an overhand right to the champion's temple, flooring him. Shogun followed up with a few seconds of ground and pound that knocked the champion unconscious.

Almost three years after entering the UFC on a wave of promise, Shogun had finally arrived.

Check out these other Defining Moments:

The Machida Era

The Gracie Hunter

The Return of the King