The 27 year-old, who previously won belts at 105 and 108lbs, dropped Akira Yaegashi in the third and ninth rounds before referee Michael Griffin was forced to end the Tokyo contest.
In the co-feature, home fighter Naoya Inoue made a successful first defense of his WBC light-flyweight title after stopping Samartlek Kokietgym in the eleventh round.
Inoue, 21, who goes by the nickname ‘Monster,’ claimed the world title in just his pro sixth fight and is widely tipped as a future multi-weight world title holder.
The Japanese fighter proved too hot for Kokietgym to handle, and having put the Thai challenger on the canvas twice previously, put a stop to the encounter with one round to spare.
Yokahama-based Inoue has now halted six of his seven opponents in total.
Also on the bill, Ryota Murata remained undefeated with a resounding ten-round triumph over 24 year-old Mexican Adrian Flores. Judges carded 100-90, 99-91 and 98-92 all in favour of Murata, who moves on to 5-0 having gone the distance for the first time since entering the paid ranks.
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