SENDAI - Japan's Shinsuke Yamanaka knocked out Tomas Rojas of Mexico on Saturday to defend his World Boxing Council (WBC) bantamweight title.
The knockout came 36 seconds into the seventh round. It was Yamanaka's second successful defence of the title he won in November last year, improving his record to 17 wins, including 12 KOs, and two draws.
Rojas, 32, and ranked seventh in the WBC, now has a record of 39 wins, including 26 KOs, against 13 defeats, one draw and one null and void.
Meanwhile, Japan's Toshiyuki Igarashi held on to his World Boxing Council (WBC) flyweight title with a narrow victory over Nestor Narvaes of Argentina on Saturday.
The 28-year-old defending champion, bleeding from both eyebrows, suffered a one-point penalty for butting, but connected with more punches.
"It was a narrow win. It was tougher than I had expected in my first defence of the title. I couldn't fight well at all," said Igarashi, who improved his record to 17 wins, including 10 KOs, with one defeat and one draw.
Narvaes, 30, who is ranked seventh by the WBC, had stood at 19 wins, including nine KOs, with two draws and one null and void.