Amy Yang of South Korea completed a third-round, 7-under 65 early Sunday to take a five-stroke lead into the final round of the rain-hit LPGA Thailand tournament.
Yang had a three-round total of 18-under 198 on the Siam Country Club's Pattaya Old Course.
The South Korean golfer had to play the final five holes of her third round on Sunday after darkness suspended play late Saturday.
So Yeon Rgu, the 2011 U.S. Women's Open champion who already completed her third round on Saturday with a 68, was in second place.
Moriya Jutanugarn of Thailand's 67 pulled her into a tie for third with South Korean Kim Sei-young (68) and Shanshan Feng, who shot 71. They were seven strokes behind Yang.
Danielle Kang (70) and Cristie Kerr (71) were the top Americans, in a group tied for ninth and nine strokes out of the lead.
The leaders were scheduled to tee off in the fourth round just before midday Sunday, with officials hoping for late afternoon finish.