Olympic champion Ishii asks "Terminator" for a fight

TOKYO (Reuters) - Japan's Olympic gold medallist Satoshi Ishii has quit judo to become an "ultimate fighter" and take on rivals with names such as a "Goliath" and "Terminator."

The 21-year-old, who won heavyweight gold at this year's Beijing Olympics, is the third Japanese Olympic champion to make the switch to professional mixed martial arts.

"This is a new chapter for me and I'll be starting from the bottom," Ishii told Tuesday's Japanese media. "I'll start with a white belt (for beginners).

"Mixed martial arts has the strongest fighters in the world and I wanted to compete against them before winning Olympic gold. My goal is to become one in six billion."

Derived from ultimate fighting, mixed martial arts is known as "kakutogi" in Japan and combines techniques from karate, judo, boxing and other hand-to-hand combat sports.

Hidehiko Yoshida, a gold medallist from the 1992 Barcelona Olympics, and 2000 Sydney champion Makoto Takimoto also made the switch from judo to kakutogi, which is hugely popular in Japan.

Historians claim the earliest form of the sport was introduced at the ancient Olympics 648 B.C. as Greek "pankration" and was also adopted as a favourite pastime by the Romans.

Ishii wants to challenge the likes of Croatian Mirko "Terminator" Filipovic or 7ft 2in South Korean Choi Hong-man, dubbed "Techno Goliath" by media and fans.

The current mixed martial art heavyweight champion is a Russian called Fedor Emelianenko, who goes by the nickname of the "Last Emperor."