Nashiro, who turned professional in 2003, was one of the fastest risers in Japanese professional boxing. In just his 5th pro bout he beat Hidenobu Honda, a 2-time world title challenger, a fight later Nashiro claimed the Japanese Super Flyweight title before winning the WBA belt in just his 8th pro bout by stopping the experience Martin Castillo. At the time Nashiro tied a national record for fewest fights to a world title, drawing level with both Satoshi Shingaki and Joichiro Tatsuyoshi.
Unfortunately Nashiro's reign didn't last long and he lost the title in his second defense when he was upset be Venezuela's Alexander Munoz.
Nashiro would regain the title by out pointing Kohei Kono, who incidentally holds that very same title today. After 2 defenses in his second reign he was out pointed by Hugo Fidel Cazares.
Despite losing the title for a second time Nashiro remained a world ranked fighter and would subsequently fight Tomas Rojas, Suriyan Sor Rungvisai, Tepparith Kokietgym and Denkaosan Kaovichit in world title or interim world title fights. Unfortunately he lost to all 4 of those men.
In a short 26 fight career Nashiro fought some of the best Super Flyweights of his era and can certainly retire with his head held high.
As well as announcing his retirement Nashiro also announced that he was joining the staff at Kinki University where he will now train amateurs fighters. The university officially appointed him on April 1st, which helped Nashiro makes his decision to retire rather than seek hunt one more world title bout.
(Photo courtesy of http://www.610gym.com/)