[1] As a student, Okada won the All Japan Industrial High School Judo League Championship four times.

Ochiai trained with former Shooto founder Satoru Sayama and got to participate in his Ultimate Boxing event, a month later he debuted in Pride, fighting Ricco Rodriguez in a losing effort.

His performance, however, was remarkable, defending multiple submission attempts and only being taken down for a failed judo throw, until he was submitted by smother choke.

He continued fighting for Pride, defeating karate stylist Soichi Nishida and professional wrestler Tomohiko Hashimoto, as well as Pancrase exponent Kim Jong Wang.

Okada's August 13 wake was attended by Masaaki Satake, Nobuhiko Takada, Kazushi Sakuraba and World Japan Management Director Katsuji Nagashima.