5 Boxers Who Transitioned to MMA

Within the combat sports arena, there are always athletes who attempt to excel in just more than their chosen discipline. Perhaps great success in their own sport gives them the confidence to learn a few more skills before trying their luck in a new combat discipline. Maybe they think success in a second sport will boost their earning potential or status. It could be they are just highly competitive and motivated and want to continue challenging themselves.

Whatever the reasons, history shows that fighters from one discipline do cross over to another despite the vast differences between the sports. Here is a look at five boxers who moved from the squared circle to the MMA octagon.

Amanda Serrano

A seven-weight world champion in boxing, Puerto Rican Serrano, who resides in Brooklyn, New York, expressed interest in participating in MMA due to the poor salaries female boxers earned in the mid-2010s. By incorporating kickboxing and Brazilian jiu-jitsu into her training regime, Serrano was preparing to test herself in the octagon.

Eventually, she got her wish, signing with the Combate Americas promotion and fighting her debut under that umbrella in April 2018. She fought one more MMA bout with Combate Americas and another with the iKON Fighting Federation. These bouts took place in 2018 and 2021 respectively. Since 2021, Serrano has focused solely on boxing. Her current record in MMA is two wins and one draw.

Holly Holm

From 2002 to 2013, Holm compiled a 33-2-3 record in professional boxing. She won world titles at light welterweight and welterweight and is highly regarded among boxing observers for her abilities and achievements in the sport. Before Holm ended her boxing career, she started competing in MMA on some small promotions. After seven bouts, she was signed up by the UFC, regarded as the top MMA promotion in the world.

In the UFC, Holm is a former bantamweight champion. Winning that title in 2015 by defeating Ronda Rousey made Holm the first fighter to have won a boxing world title and a UFC world title. Holm is still active today. Her MMA record currently stands at 15 wins and 6 defeats.

Eric “Butterbean” Esch 

From 1994 to 2013, Esch compiled a professional boxing record of 77-10-4. Esch boxed in the heavyweight division and was very heavy – between 320-350 pounds. Because of this, he was known as “The King of the Four Rounders” and developed a cult following. His short bouts usually ended in a KO, one way or another. His moniker “Butterbean” also brought him further popularity.

Esch fought on the undercards of some big bouts, including a September 1995 card at Caesars Palace, which featured Oscar De La Hoya, Kevin Kelley, Erik Morales, James Toney, and Johnny Tapia.

After moving into kickboxing, “Butterbean” tried his hand in the MMA arena, beginning in 2006. Fighting on promotions such as K-1 Premium and Pride Fighting Championships, Esch had his final MMA contest in 2011. His MMA record stands at 17 wins, 10 losses and one draw.

James Toney

One of the most accomplished boxers of all time, Toney boxed from 1988 until 2017, winning world titles in three separate weight classes. In 2010, Toney gave MMA a try. His boxing fame secured him a multi-fight contract with the UFC.

Toney was matched with UFC legend Randy Couture, who defeated him in the first round of their August 2010 encounter. From signing his UFC contract to facing Couture, Toney only had six months to prepare. It would be the boxer’s only appearance in the MMA arena.

Ray Mercer

Mercer is another boxing legend who made a one-fight-only visit to MMA. Ray Mercer boxed in the heavyweight division between 1989 and 2008. He held a version of the world title in 1991. He was also an Olympic gold medalist in the heavyweight division at the 1988 Games. Mercer explored some options within kickboxing and MMA as his boxing career drew to a close.

Mercer’s MMA experience was brief but successful. In June 2013, he defeated former UFC heavyweight champion Tim Sylvia at an event called “Adrenaline 3: Bragging Rights.” Mercer walked away with the MMA bragging rights that evening after knocking Sylvia out with a right hand after only 9 seconds. It would be the only time Mercer would officially fight an MMA bout.

Colin Morrison

A boxing fan since his teenage years, Morrison began writing about the sport in July 2016. He appreciates all styles of boxing and has nothing but respect for those who get in the ring for our entertainment. Morrison is from Scotland and can be found on Twitter @Morrie1981.

See author's posts