WBC superflyweight champion Masamori Tokuyama is set to hang up his gloves and retire after his scheduled world title defense against American Jose Navarro in Osaka next spring, boxing sources said Friday. Tokuyama, who reclaimed the WBC crown in a unanimous decision over Katsushige Kawashima of Japan in July this year, had been wavering over whether to call it quits and initially decided to continue with his fighting career in November. After recapturing the title, however, Tokuyama cited a lack of enthusiasm and decided to bring an end to his career with his bout against Navarro.