Katie Burnett, whose lone top 10 finish on the LPGA Tour came two years ago, birdied the final hole Friday for a five-under 67 and a one-shot lead at the Lotte Championship.
The world number 195 had a bogey free third round to take a 13-under 203 total into Saturday's final round at the Ko Olina course in Kapolei, Hawaii.
Burnett, from the United States, has a one shot lead over South Korea's Jang Su-Yeong. Her only top 10 finish came in 2014 on the same course. She has not won a tournament in 59 previous starts.
"It was a solid round," said the 26 year-old Burnett. "I just tried to stay patient. I had a few opportunities early that I let slip by. Then I just really focused on the back nine, just staying with my process and being patient and knowing that eventually I would make a few birdies."
Burnett began the round two shots out of the lead before moving up the leaderboard with birdies on the fifth, 11th, 14th and 15th holes.
The 21-year-old Jang shot a 67 that included four straight birdies to finish the front nine, and a burst of three birdies between two bogeys on the back nine. She is playing in her first USA event this week.
Defending US Women's Open champion Chun In-Gee fired a 65 and is tied for third at 10-under in just her second start after a freak collision with a suitcase that sidelined her for a month.
Chun was riding the escalator at Singapore's Changi Airport when she was struck by the suitcase that got away from the father of fellow South Korean Jang Ha-Na. She sat out with an injured back but tied for second two weeks ago in her return.
Chun is tied with Thailand's Moriya Jutanugarn, who has shot rounds of 68, 70 and 68.