Akie Iwai produced her worst round of the tournament on Thursday but still emerged with the lead entering the final day of the Lotte Championship in Ewa Beach, Hawaii.
The 23-year-old Japanese player shot a 1-under-par 71 in the third round at Hoakalei Country Club, ending up at 13-under 203 for a one-stroke edge.
Second-round leader Youmin Hwang of South Korea shot a 75 in the third round, leaving her in an eight-way tie for second at 12 under.
Hwang is level with Meghan Khang (third-round 67), Brooke Matthews (69), Jessica Porvasnik (72), Japan's Minami Katsu (66), South Korea's Hyo Joo Kim (66), Taiwan's Peiyun Chien (68) and Thailand's Pornanong Phatlum (69).
World No. 2 Nelly Korda (69) and Japan's Nasa Hataoka (71) share 10th place at 11 under.
Iwai led after shooting 64 on Wedn