SENDAI, Japan (AP) -- Shinsuke Yamanaka of Japan stopped Mexico's Tomas Rojas 36 seconds into the seventh round on Saturday to retain the WBC bantamweight title.

Yamanaka (17-0-2, 12 KOs), making his second defense of the title he won in April, sent the challenger to the canvas with a left and Rojas (39-14-1) was unable to move for several minutes but left the ring under his own power.

In another bout, Japan's Toshiyuki Igarashi (17-1-1, 10 KOs) outpointed Argentina's Nestor Narvaes (19-1-2) in his first defense of his WBC flyweight title.

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