[6] YA-MAN won the fight by a first-round technical knockout, stopping Kazuyoshi with eight seconds left in the opening round.
[8] He won the fight by split decision, with scores of 29–28, 28–29 and 29–27,[9] YA-MAN advanced to the tournament finals, held on the prelims of RISE 128 on November 2, 2018, where he faced Taiki Sawatani.
He was booked to face the 2019 Shinkarate K2 Grand Prix winner Ryota Saito at Stand up Kickboxing Vol.1 on December 22, 2019.
YA-MAN's fight with Yamaguchi was one of two such matches held at the event, with RISE representative Takashi Ito stating he would introduce an OFG belt and rankings, should it prove to be popular enough.
[18] During the press conference, YA-MAN revealed that he had volunteered to fight under this rule-set, although he remained respectful of his opponent, stating: "...I hope Yuma Yamaguchi is coming in with a mentality like 'If I lose to a guy like this [who's only been training for five years], I'm getting weaker, and it's probably best I retire soon'".
He continued pressuring when the fight action resumed and was able to rally back in the second round, as he knocked Yamaguchi with a left uppercut to a right hook combination.
Yamaguchi was unable to beat the eight-count following the knockdown, forcing the referee to wave the fight off at the 1:53 minute mark.
[20] YA-MAN stated his desire to fight the winner of the other OFG bout on the card, between Yuma's brother Hiroto and Yoshimichi Matsumoto.
[21] On August 24, 2021, several additional bouts were announced for Rise World Series 2021 Yokohama, which was scheduled to take place on September 23, 2021.
[22] On September 22, the two fighters were engaged in a brief onstage scuffle during the face-offs, in which Kitai initiated physical contact when he shoved YA-MAN.
[25] On September 24, 2021, a day after the RISE WORLD SERIES 2021 Yokohama event was held, YA-MAN called out Kan Nakamura over social media.
[28] On November 15, 2021, in a Twitter post, Kouzi named four fighters he wished to face at the Rizin FF New Year's Eve event: Genji Umeno, Taiga, Shibatar and YA-MAN.
It was YA-MAN's first fight not contested under the "open finger glove" rules since his decision loss to Taishi Hiratsuka on February 28, 2021.
The fight was scheduled for the undercard of Rise El Dorado 2022, which took place on April 2, 2022 at the Yoyogi National Gymnasium in Shibuya, Tokyo.
Ito was however able to beat the ten count and knocked YA-MAN down in turn, with a well placed left straight soon after the action resumed.
[37][38] On May 19, 2022, at a joint press conference held by K-1 and RISE, it was announced that YA-MAN would face Ryusei Ashizawa on the undercard of the Tenshin Nasukawa vs Takeru Abema pay-per-view, which took place at the Tokyo Dome on June 18, 2022.
[42][43] During the post-fight press conference, YA-MAN stated his desire to compete in mixed martial arts by the end of the year.
[48] YA-MAN faced the two-time Rizin Featherweight title challenger Mikuru Asakura at the inaugural "Fight Club" event.