in 2004, in a winning bout against Canadian fighter Joe Doerksen. After that Riggs moved down to Welter Weight to fight veteran Chris "Lights Out" Lytle. Riggs went on to win the fight by 2nd-round TKO. And was the 1st and only man to ever stop the very popular battler Chris Lytle. Then after being named the UFCs number 1 Welter Weight contender. Riggs received his shot at the UFC Welterweight Championship at UFC 56 in November 2005 against Matt Hughes. He was originally supposed to face the winner of the upcoming title fight. But got called to fight just a month after the defeating Lytle in UFC 55 to face long time champion Hughes for the UFC Welter Weight title. Originally, the title shot was offered to Karo Parisyan, who had to withdraw due to a torn hamstring. When Riggs was contacted to take Parisyan's place he jumped at the chance, despite having fought at UFC 55 just a month earlier. However, Riggs did not make the required weight and the fight was declared a non-title event, due to Hughes allowing Riggs to fight him (if a fighter does not make weight for a match, the match may still take place if their opponent allows it). Despite his efforts, Riggs could not mount a significant challenge; Hughes took him down and submitted him with a kimura from half-guard just minutes into the first round of the fight. Following his loss to Hughes, Riggs rebounded to win against future longtime Strikeforce Welterweight Champion, Nick Diaz via decision at UFC 57. In the hospital room after the fight, Diaz and Riggs got into a physical altercation where they had to be separated by police. Riggs then moved up to Middleweight to face The Ultimate Fighter alumnus Mike Swick. Early in the fight Riggs was caught in a guillotine choke and tapped out. Riggs then fought The Ultimate Fighter 2's Jason Von Flue, submitting him with a triangle choke. Riggs' last UFC bout was on December 13, 2006, against Welterweight contender Diego Sanchez at UFC Fight Night 7. Riggs lost the fight due to knockout from a hook followed by a knee in 1:45 of the first round. Following the fight with Sanchez, Riggs chose to go to the WEC and compete for the vacant WEC Middleweight Championship, but had to pull out of the fight the day before because of a