“Krazy Bee” Miyuu Yamamoto makes his professional boxing debut at the age of 51

Japanese martial arts veteran “Krazy Bee” Miyuu Yamamoto will enter the boxing ring for the first time as a professional at the age of 51 when she faces Australian Michelle Mack on March 28 in Sydney. The fight will be contested at a catchweight of 51.0 kilograms, spread over six rounds of two minutes each.

At the age of 51, RIZIN’s Miyuu Yamamoto jumps to the Ring for his professional boxing debut

Yamamoto announced the decision following her MMA retirement at RIZIN 45 on December 31, 2023, where she lost in the second round to undefeated super atomweight champion Seika Izawa via rear choke. The then 49-year-old told officials that she had continued to train in boxing during her retirement from mixed martial arts.

In an official statement released at the event websiteYamamoto revealed the depth of her connection with boxing during her martial arts career. “Even when I was doing MMA, I found myself watching boxing all the time,” she said. The three-time world freestyle wrestling champion explained that boxing had become such an important part of her life that she continued training after leaving MMA, believing she would eventually compete in the sport.

Yamamoto initially approached the opportunity with modest expectations. “At first I thought if I could only play one match, I wouldn’t regret it,” she explained. However, her mentality changed once the fight was confirmed. “Now that the match has been decided, that feeling has completely changed. All I have now is the determination to win this match,” she said.​

The decision represents a new chapter in a career marked by late-blooming athletic achievements. Yamamoto began her MMA career at the age of 41 in 2016 after an extensive wrestling background, including world championships in 1991, 1994 and 1995. She compiled a 6-8 professional MMA record entirely within the RIZIN Fighting Federation, competing against top atomweight fighters including Ayaka Hamasaki, Seo Hee Ham and Kanna Asakura.

Her father, Ikuei Yamamoto, represented Japan in wrestling at the 1972 Munich Olympics. Her late brother, Norifumi “Kid” Yamamoto, became a Japanese MMA legend before his death in 2018. Her sister, Seiko Yamamoto, won four consecutive world wrestling championships from 1999 to 2002. Her eldest son, Arsen Yamamoto, also competes as a mixed martial artist in RIZIN.

While Yamamoto’s boxing debut at age 51 is exceptional, it falls short of the official record for oldest female professional boxing debut. Mexico’s Patricia Trejo Ruiz holds the Guinness World Record after starting her professional boxing career at the age of 51 and fighting until she was 54.

Yamamoto trains at the Krazy Bee gym, the facility founded by her late brother. She currently lives in Guam with her husband Kyle, who owns coffee shops on the island. Australian opponent Michelle Mack recently announced her return to competition on social media, noting that the fight would feature an “experienced professional MMA international opponent” at a catchweight.

Yamamoto expressed hope that her endeavor would inspire others. “If this challenge can give people the strength to take one more step forward in their own lives, nothing would make me happier,” she said.