Thales Leites Lourenço[4] (Portuguese pronunciation: [ˈtaliʒ ˈlejtʃiʃ]; born 6 September 1981) is a retired Brazilian mixed martial artist best known for competing in the middleweight division of the Ultimate Fighting Championship.

[5] Leites made his mixed martial arts debut at Shooto Brazil in 2003, defeating Felipe Arinelli by arm-triangle choke submission.

Leites would win his next two fights in Vitória before making his debut in the United States in Hawaii's Rumble on the Rock promotion in 2005, where he defeated Adam Roland in his fourth consecutive mixed martial arts victory.

After a successful outing in the U.S., Leites returned to Brazil to fight Gustavo Machado, who was coming off two wins in the Japanese Pancrase organization.

Leites defeated the more experienced Machado by submission in the third round, and was invited back to Rumble on the Rock to fight Hawaiian Ronald Jhun in September.

In September 2006, it was announced that Leites would make his UFC debut against veteran middleweight Nate Marquardt at Ortiz vs. Shamrock 3: The Final Chapter.

Leites made his debut at The Ultimate Fighter 4 Finale, where he lost a unanimous decision to Danish kickboxer Martin Kampmann.

Leites next earned a submission victory over Floyd Sword at The Ultimate Fighter 5 Finale by arm-triangle choke.

[7] Leites accepted the fight after Travis Lutter, Jensen's original opponent, was forced to withdraw from the event.

[8] Leites defeated Jensen by armbar submission in the first round, raising his UFC record to 3 wins, 1 loss.

The lack of action during the fight at one point caused referee Marc Goddard to state to the fighters that Mixed Martial Arts was a "contact sport".

Just days later, Dana White revealed to Yahoo Sports his unawareness of McCrory and Leites' release from the UFC and expressed his intentions to reverse those actions.