She ended at 14-under-par 202, two better than Chella Choi (6-under 66).
Second round co-leaders Yuki Ichinose and Mamiko Higa each registered a 2-under 70 Sunday at Kintetsu Kashikojima Country Club, ending in a tie for third place at minus-10.
Shiho Oyama, who also had a piece of the second-round lead, stumbled to a 1-under 71, settling for a fifth-place tie with Yumiko Yoshida (68) at minus-9.
Defending champion Stacy Lewis managed a 2-under 70, end in a three-way tie for eighth at minus-7.
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