Women's WBC atom weight champion Momo Koseki beat WBA light minimum title holder Ayaka Miyao by unanimous decision in a unification bout in Tokyo on Thursday.
Koseki defended her title for a 16th time, a record for a Japanese boxer in the men's or women's game. Miyao was aiming to defend her title for a sixth time.
Koseki, 33, improved her record to 21-2-1 (seven knockouts). Miyao, 32, dropped to 20-6-1(four KOs).