South Korea's A Lim Kim made a hole-in-one to finish the front nine on Friday, then closed with back-to-back birdies while grabbing a one-stroke lead after three rounds at the Lotte Championship in Ewa Beach, Hawaii.
Kim wound up with a 5-under-par 67 at Hoakalei Country Club, leaving her at 14-under 202 entering the final round on Saturday.
Russia's Nataliya Guseva is one stroke back following a 68, and Ryann O'Toole is at 11 under following a 69.
Auston Kim (third-round 69), South Korea's Jin Young Ko (67) and second-round co-leader Yuri Yoshida of Japan (71) are tied for fourth at 10 under.
South Korea's Jeongeun Lee5 (67) and Japan's Nasa Hataoka (69) share seventh place at 9 under. South Africa's Ashleigh Buhai (67) and defending champion Grace Kim of Australia (68) are at 8 under, tied for ninth.
At the par-3 ninth hole, A Lim Kim sent her 9-iron shot onto the green, and it took one hop into the cup.
She said of the hole, "Calculate number and then chose line and then hit it. I think (it was) 99 per cent lucky."
Looking ahead to the final round and the chance to add to her one career LPGA victory, at the 2020 US Women's Open, A Lim Kim said, "Every tournament I think same: Focus on my line and then hit it. That's it. Any result, I don't care."
A Lim Kim sits in 65th place in the tour standings, and she needs to climb up to the top 60 between this week and next week to qualify for the season-ending CME Group Tour Championship in Naples, Fla.
Guseva, a 21-year-old rookie who played for the University of Miami, is aiming to make history as the LPGA's first Russian winner. She made five birdies on Friday before logging her lone bogey at the par-4 17th hole.
"It's been my first time playing in the final group and it's different feeling, but the most important thing is I had fun out there," Guseva said. "I didn't really think about winning anything or doing something special today. ...
"I will just try and keep that momentum going and just, yeah, enjoy myself."
O'Toole's third round featured four birdies and a single bogey.
"Trying to back up 6 under (on Thursday) is not always easy, so sometimes you just get frustrated ... so I really had to make myself just take it as it came and be patient," O'Toole said. "So I think that helped me at least get to 3 under and keep myself in it."