Friday at Japan's Mecca of fightsport, Korakuen Hall, Shooto's afroed ace continued his ascent in the Shoot Boxing ring.

The fourth edition of Shoot Boxing's Bushido series witnessed Mamoru Yamaguchi taking a three-round unanimous decision over Masahiro Fujimoto. The perennially elite MMA flyweight used clean punching and defense -- as well as a one-arm shoulder throw for a Shoot point in the second round -- to earn scores of 30-28 and 29-28 from the judges. The win was Yamaguchi's fourth appearance in the promotion, all within the last seven months, and pushed his Shoot Boxing mark to 3-1.

An offshoot from the same combat sports family tree as Shooto, Shoot Boxing promotes "standing vale tudo" events that feature the full complement of punches, kicks, elbows and knees in addition to throws and standing submissions.

The Shoot Boxing ring has proved a crucial outlet for the 32-year-old Yamaguchi. Though he's one of pro Shooto's biggest stars, and the only fighter to hold Shooto world titles in two weight classes (both at 123 and 132 pounds), he has been put in a difficult professional circumstance in regards to his MMA career. In July 2008, he was choked out in his third meeting with rival and Shooto 123-pound champion Shinichi "BJ" Kojima. With a fourth bout between the two promotionally unappealing, and Shooto promoters not wanting to risk the veteran knocking off up-and-coming challengers (as he previously did with Yuki Shojo and Masaaki Sugawara last year), his handlers decided that testing his striking acumen in Shoot Boxing was the best step forward for his career.

Of related importance, the event also saw Shoot Boxing 121-pound champion Phantom Shinya earn a second-round doctor stoppage over interim champion Noriyuki Enari to unify the titles. However, Enari was actually defeated by Yamaguchi in his Shoot Boxing debut in February, and so coupled with this most recent victory, the former two-time Shooto world champion may have earned himself a chance to become a Shoot Boxing champion, as well.

The card was also scheduled to feature another MMA fighter, hot featherweight prospect Tyler Toner, coming off of his surprise first-round knockout of 2006 S-Cup champion Kenichi Ogata in June. Toner was scheduled to face Shoot Boxing 154-pound champion Takaaki Umeno in a non-title bout, but was pulled from the card late this week for undisclosed reasons, and replaced with German Florian Schopp, who was knocked out with a left hook in just 34 seconds.