CHIBA, Japan — Japan's Takefumi Sakata defeated compatriot challenger Shingo Yamaguchi with a unanimous decision today to defend his WBA flyweight title.

Sakata dominated the late rounds and improved to 32-4-2 with 15 knockouts in his third successful defense of the title he won in March, 2007 with a technical knockout of Venezuela's Lorenzo Parra.

Yamaguchi, who was making his second attempt at a world title and first since 2002, fell to 22-5-2 with eight KOs.