Japanese boxer Nobuo Nashiro, former World Boxing Association super flyweight champion, is putting his career on the line in September, when he will challenge Tepparith Singwangcha of Thailand, the current title-holder.

Nashiro (photo, left) says this will be his last fight as a challenger. If I lose, I’m going to retire. I’m determined to pour everything I have into it. I don’t want to regret,” he said.

The 30-year-old boxer will face Singwangcha in Osaka, on September 1st, according to his handlers.

Nashiro became champion in July 2006 and held the title until May 2010, when he lost it to Hugo Cazares from Mexico.

Tepparith Singwangcha, 23, became interim champion in May 2011 and was promoted to full champion several months later, in November. The previous champion, Japan’s Tomonobu Shimizu, had to give up his title following an eye injury.