Chris Leben

Leben made his debut for Bare Knuckle Fighting Championship on April 6, 2019. He faced Justin Baesman in the show's co-main event. Leben won the fight via knockout just 25 seconds into the first round.

Leben was supposed to face Brennan Ward at BKFC 6 on June 22, 2019. On June 12, news surfaced that Ward withdrew from the bout and was replaced by Dakota Cochrane. Leben lost the fight by unanimous decision.

In late 2018 Chris came out of retirement after being given all-clear by doctors.

After a return to MMA never materialized, Leben instead turned to bare knuckle boxing. He faced Phil Baroni at the World Bare Knuckle Fighting Federation debut card on November 9, 2018. He won the fight via TKO in the first round. In March 2019, reports surfaced that Leben had sued WBKFF for $90,000 in unpaid salary.

Leben and his fiancé Brittany have a son, Liam (b. 2017).

After two years away from active competition for Leben, it was announced by Scott Coker on Inside MMA that Leben had signed a multi-fight deal with Bellator MMA in February 2016. However, after undergoing a physical to be cleared, he failed several electrocardiogram (EKG) tests, according to the statement. Doctors discovered a "life-threatening abnormality" to the left ventricle of his heart, which was "oversized", "misshapen", and "not operating properly," thus ending any possibility of a return.

In 2016, Leben completed Herb Dean's mixed martial arts referee course, making him eligible to referee bouts in California. After refereeing in the regional circuit, Leben debuted in notable shows at Golden Boy Promotions: Liddell vs. Ortiz 3.

Having well-documented past with substance abuse, Leben claims to be sober since 2015 and is actively advocating for clean eating and healthy lifestyle.

On January 20, 2014, Leben announced his retirement from MMA competition. He will refocus on coaching at The Arena in San Diego, California. He cited an increasingly talented middleweight roster, his recent losing streak and the risk of serious injury as reasons for retiring. He called himself fortunate to have never had surgery throughout his record 22-fight middleweight stint, though he predicted several of his nagging injuries will get worse with time.

While visiting his brother at work one day, Leben noticed an MMA gym located across the street, home to Team Quest. Trainer Robert Follis accepted Leben into the team, and soon Leben was training with Randy Couture, Matt Lindland, Nate Quarry, and Ed Herman. After refining his talent, Leben began fighting as an amateur, achieving a record of 5–0, and capturing the FCFF and UFCF middleweight titles.

His next fight was against Michael Bisping at UFC 89, which he lost by a unanimous decision after a full three rounds. Leben taunted Bisping throughout the last two rounds by dropping his arms and raising his chin. The judges scored the fight 30–27 (twice) and 29–28 for Bisping. Bisping used effective counter punching in the fight to keep the aggressive Leben at bay. Both fighters showed sportsmanship by congratulating one another and raising each other's arm after the fight. After the fight with Bisping, Leben tested positive for Stanozolol and was suspended for nine months and fined a third of his fight purse. He was eligible to return in July 2009. Leben admitted he had used the substance several months prior to the fight, but stated he had assumed it would have been out of his system by then.

Leben fought Andrew Craig and lost by split decision on July 6, 2013 at UFC 162.

Leben faced Uriah Hall on December 28, 2013 at UFC 168. After almost being knocked out at the end of the first round, Leben told his corner that he was done, taking a TKO loss to Hall after the first round. UFC commentator Joe Rogan pointed out during the broadcast that Leben asked, "Was I knocked out?" as he was being led to his corner. Leben then reiterated "I'm done" multiple times before the fight was waved off. This marked Leben's fourth loss in a row.

Leben's return fight was expected to be against Karlos Vemola on December 29, 2012 at UFC 155. However, Vemola was forced out of the bout and replaced by promotional newcomer Derek Brunson. Leben was defeated via unanimous decision.

Leben faced Brian Stann on January 1, 2011, at UFC 125 He lost the fight via TKO in the first round. After the fight between Leben and Stann, Leben's coach Burton Richardson says Leben's poor performance may have been caused by a sickness before the bout: "First, great job by Brian Stann. He never looked better. Many have commented that Chris was very slow and looked off last night. The truth is that Chris was sick. He had a fever and chills when he stepped into the cage. He was vomiting in the locker room before the fight, and after a hard warm up he didn't have a drop of sweat. Big heart to fight like that, but he was moving slow motion. He was very sharp in training. He will be back."

On April 4, 2011, the UFC announced that Leben's next opponent would be Wanderlei Silva with the two scheduled to meet on July 2, 2011 at UFC 132. Leben knocked out Silva with consecutive uppercuts from the clinch, 27 seconds into the fight, resulting in the fastest knockout win in Leben's career.

Leben faced Mark Muñoz on November 5, 2011 at UFC 138, losing by TKO at the 5:00 mark of the 2nd round due to a cut on his left eyebrow and left him unable to see and forced a corner stoppage. On November 28, 2011, Zuffa LLC, owner of the Ultimate Fighting Championship, released information stating that Leben tested positive for oxycodone and oxymorphone following his loss to Muñoz at UFC 138. As a result of the positive test, Leben was suspended from fighting for 1 year.

Leben then faced Jay Silva on January 11, 2010, at UFC Fight Night 20, winning via unanimous decision (30–27, 30–27, 30–27).

Leben was expected to face Aaron Simpson at UFC 114, but the bout took place on June 19, 2010, at The Ultimate Fighter: Team Liddell vs. Team Ortiz Finale. After a rough first round where Simpson slammed Leben a couple of times, Leben eventually connected consecutive punches on Simpson in the second that sent him stumbling across the octagon, collapsing face first at the other side of the octagon, prompting referee Josh Rosenthal to end the fight via TKO at 4:17 of the second round.

After Wanderlei Silva was forced out of his UFC 116 bout with Yoshihiro Akiyama due to broken ribs, Leben agreed to fill in for Silva in the bout against Akiyama, and faced him two weeks after defeating Simpson. Although he was outstruck and outwrestled for most of the first round, Leben managed to stay competitive and keep a fast paced fight with the rapidly tiring Akiyama in the second round. In the third and final round, Leben capitalized and sunk in a triangle choke with just twenty seconds left in the fight, forcing Akiyama to submit. It was considered the best performance of Leben's career and one of the best fights of the year. After the fight, Leben called for a fight with Silva, saying "come on Wanderlei, I'll take you out, too!", though UFC president Dana White said in the post-fight press conference that a Leben-Silva affair is not under consideration. Leben won Sherdog.com's Comeback Fighter of the Year for 2010.

On October 20, 2010, Leben was arrested in Honolulu, Hawaii for suspicion of driving under the influence after crashing his truck into a wall off of Kapiolani Boulevard. He was released from custody after posting bail.

On April 30, 2008, Leben was arrested in Oregon by Clackamas County Sheriffs for a DUI stemming from an earlier date. He was kept in jail and temporarily held without bond for allegedly violating his probation. Leben was then sentenced to 35 days in jail.

Leben then lost to Kalib Starnes by a very close unanimous decision at UFC 71 on May 26, 2007. The bout won Fight of the Night honors.

In May 2007, Leben moved to East Oahu, Hawaii to accept the main coaching job at Icon Fitness MMA Gym. ICON Sport promoter T. Jay Thompson said, "I am very excited to have Chris at our new facility. His energy and overall enthusiasm for the sport will add tremendously to our gym. I am very impressed with the family friendly 'outside of the cage' personality of Chris and what that will mean to our members." In addition to training at ICON, Leben and fighter Steven "The Soul Samurai" Saito opened Ultimate Fight School gym in Oahu in January, located two blocks from the University of Hawaii campus. Leben is a playable fighter in the UFC Undisputed video games. Before becoming a professional fighter, Leben worked construction and was a housepainter. Leben has a radio show called "Unfiltered MMA Radio".

After the show, Leben moved to Seattle, Washington to train with AMC Pankration. He has competed in several UFC events since the show and is the only person to have fought in the first six Ultimate Fight Night events, during which he earned a string of victories: a split decision win over future TUF 4 finalist Patrick Côté, an armbar submission against Edwin Dewees, a first-round TKO over Jorge Rivera, and a unanimous decision over Luigi Fioravanti. Leben was defeated by Anderson Silva at UFC Ultimate Fight Night 5 on June 28, 2006, by KO 49 seconds into the first round, but returned at UFC Fight Night 6 on August 17, 2006, where he defeated Jorge Santiago by knockout 35 seconds into the second round. He is the only fighter to fight at every event under the "Fight Night" banner.

On April 9, 2005, Leben fought Jason Thacker on the undercard of the live finale of The Ultimate Fighter 1. Thacker was not amused when he watched the show and found out Leben had used his bed as a urinal. Speaking with Dana White, Thacker demanded a match against Leben at the finale. The match was set up, and Leben won 95 seconds into the first round after referee stoppage due to strikes. Afterward, Leben apologized to Thacker for urinating on his bed, saying he had since given up drinking because of that sort of incident.

Christian Cyrus Leben (born July 21, 1980) is an American former mixed martial artist, referee, and current bare knuckle boxer. A professional MMA competitor from 2002 until 2013, he most notably competed in the UFC in the Middleweight division, compiling a record of 12-10 in 22 appearances for the organization. Leben first appeared in the inaugural season of The Ultimate Fighter reality series, and also fought in the now-defunct WEC. He began his UFC career with five victories in a row before suffering a knockout loss to future UFC Middleweight Champion Anderson Silva, and was known for his toughness and powerful left hand. Leben was the inaugural WEC Middleweight Champion.