Ruediger was one of three fighters on The Ultimate Fighter 5 who had previously fought inside the UFC's Octagon. Only Lauzon, of the three, had a victory in the UFC. In episode 5, Team Pulver selected Corey Hill to fight Ruediger. The episode showed Ruediger eating ice cream cake after learning of his upcoming fight, shortly before the weigh ins. He was then struggling to make the weight requirement, and let himself be dragged to and from the sauna room, but getting out before it could actually work. Ultimately, Penn and Maynard gave up and walked off as Ruediger literally begged for them to pick him back up. After displaying what could be signs of extreme exhaustion, an ambulance carried him off to the hospital. He took direct criticism from his own coaches and teammates for "taking short cuts" and displaying a lack of dedication, due to his request for a colonic to lose weight and his overall poor work ethic. The next day, Dana White dismissed Ruediger from the competition and he was ordered to leave the house. Ruediger later stated that he saw The Ultimate Fighter show as a "marketing tool" and that audience members should "take what you see on TV with a grain of salt."
Post UFC
In a March 2007 interview Ruediger says that he would be fighting "very soon" in a "large organization". In an article by Loretta Hunt at The Fight Network, it was revealed that FEG officials had a verbal commitment from Ruediger to fight Katsuhiko Nagata for their June 2K-1 Dynamite!! USA supercard in Los Angeles. Many unsubstantiated rumours appeared on the Internet regarding his failure to obtain a license to fight in California, asserting that his failure to make weight on The Ultimate Fighter was the reason. These were refuted in an interview with Armando Garcia, the executive director of the California State Athletic Commission. According to Garcia, because Ruediger was a late replacement on the K-1 Dynamite card doctors with the CSAC did not have sufficient time to review his medical information, and could not issue him a license in time for the K-1 fight. He was then cleared for a license, fighting 5 times in the state of California since his reinstatement.
Return to the UFC
After Terry Etim injured himself in preparation for his bout against Joe Lauzon at UFC 118, Ruediger signed a four fight deal with the UFC, and stepped in as Etim's replacement. The fight was selected to be shown on the Spike TV broadcast. Ruediger lost the fight early in the first round via armbar submission. Ruediger was expected to face Paul Kelly on November 20, 2010 at UFC 123. However, Ruediger was forced out of the bout with a groin injury. Ruediger faced Paul Taylor on February 5, 2011 at UFC 126. Ruediger was defeated via second round KO and subsequently released from the promotion.
Post UFC
Ruediger faced Scott "KO" Catlin on March 16, 2012 at BAMMA BadBeat 5 and lost via TKO from punches 36 seconds into the second round. Gabe fought SiriusXMradio hostJason Ellis in a celebrity boxing match at Ellismania 8 "Shave my Friends Tonight" in Las Vegas on July 14, 2012. Gabe was KO'd by Ellis in the 2nd round. Ruediger contested that Ellis had cheated by using different wraps, gloves, and headgear and stated that if they wore the same gear, Ellis would not have won the fight. Gabe then requested a rematch with Ellis and the two fought at Ellismania 9. Gabe lost the decision 29-28, and was generally dominated by Ellis.
