American Lexi Thompson claimed her seventh LPGA title as she stormed to a six-shot victory in the LPGA Thailand.
The 21-year-old from Florida started the final round with a four-shot advantage at the Siam Country Club and she extended that thanks to a four-under 68 to finish on 20-under 268.
However, the day was not as straightforward as it appears for Thompson as South Korea's In Gee Chun, who was second overnight, mounted a strong challenge on the front nine.
Chun, winner of the US Women's Open last year, kicked off with three successive birdies to close within one shot of Thompson and she was still only two adrift as they reached the turn after the American bogeyed the ninth.
The pivotal hole proved to be the par-five 10th which Thompson eagled to go three clear as Chun could only manage a birdie.
The South Korean then mixed three bogeys with two birdies on the back nine before a double-bogey at the 17th ended her challenge and left her with a two-under 70 and second place on 14 under.
Thompson, meanwhile, coasted through the back nine, adding one further birdie on the 15th, to become the first American winner of the tournament.
"I never like to count it as a win until it's over. I just try to play aggressive and play my best out there," said Thompson.
"I was just saying I had to make birdies to win this thing. She was playing unbelievable with a three-birdie start there, and I knew I had to make birdies to stop her. I was just trying to focus on my game and nobody else's out there."
Thompson's win ensures she will leapfrog compatriot Stacy Lewis to become the top-ranked American woman at No 3 in the world.
Jessica Korda of the United States fired eight birdies for a 64 and a 13-under total of 275, giving her a share of third place along with defending champion Amy Yang of South Korea, who signed off with a 70.
Britain's Charley Hull finished in a tie for 30th place on one under after closing with a one-over 73.