Rizin has announced that a mother and son will be competing on the same card, a first for a major MMA promotion.
Miyu Yamamoto, 41, will be making her MMA debut on the same card as her son, Asen Yamamoto, 19.
Both are members of an elite family of Japanese wrestlers, including patriarch Ikuei Yamamoto, who competed in the 1972 Olympics. Miyu is also the older sister of Seiko Yamamoto, a four-time world champion, and Norifumi "Kid" Yamamoto, a UFC fighter and one of Japan's most popular MMA stars.
Miyu became a world champion at the age of 17, and later won two more world championships. Her son Asen made his debut on Rizin's New Year's Eve show, losing to Kron Gracie.
The Rizin card takes place on September 25 at the Saitama Super Arena.