RIZIN 42 was a combat sports event that took place on Saturday, May 6, 2023 at the Tokyo Ariake Arena in Tokyo, Japan.

Notable RIZIN names Yusuke Yachi and Tsuyoshi Sudario were among the 14 names announced for RIZIN 39 on Wednesday. The new matchups are joining a card that take place on October 23rd at the Marine Messe Fukuoka Hall A in Fukuoka, Japan. Yachi will have a tough challenge in his attempt to snap a losing streak. He is being paired up against South African lightweight talent Boyd Allen, who will be fighting in the promotion for the first time. Allen has a pro record that includes 16 wins through 21 appearances. He has fought numerous times in notable regional promotion EFC since 2012.