New Zealand golfer Lydia Ko had a strong finish to the LPGA Thailand to finish in a tie for 8th.
Ko, the world number one had successive rounds of 68 to finish 11 under for the tournament, 11 shots behind Amy Yang of South Korea.
Yang sank a short birdie putt on the 72nd hole to seal a five-stroke victory, claiming the title for a second time with a new tournament record.
The 2015 champion closed with a four-under 68 at the Siam Country Club in Chonburi to finish with a 22-under-par total of 266, one shot lower than the previous record and well clear of nearest rival, fellow Korean Ryu So-yeon (68).
Compatriot Kim Sei-young finished a further two strokes back in third place, while Americans Lexi Thompson and Danielle Kang shared fourth place alongside another Korean, Chun In-gee, on 13-under-par at the rain-hit event.
Frustrating weather delays during the first three rounds left the players either battling boredom or needing to play almost 36 holes in a day, but Yang stayed focused throughout to claim a third LPGA title after leading for all four days.
Starting her final round with a five-shot cushion, Yang always appeared in control of her destiny but when Ryu threatened to cut her lead to just two strokes on the back-nine, the 27-year-old produced a pair of title-winning shots.
Yang made a complete mess of her chip from beside the green on the par-four 14th but breathed a huge sigh of relief when she drained a difficult 20-foot downhill putt to match Ryu's par and keep her advantage at a manageable three shots.
Still pumped by the adrenaline of her clutch par-save, Yang sent a booming drive into the centre of the green on the short par-four 15th and was able to extend her lead by another shot with a tap-in birdie as Ryu's challenge faded with a par.