World number one Nelly Korda dropped off the pace to finish fourth at the Tournament of Champions and allow American Danielle Kang to claim victory.
Kang, 29, shot a four-under-par 68 after starting the final round one adrift of Korda in Orlando, Florida.
The season-opening triumph was Kang's first LPGA title since winning the Marathon Classic in 2020.
England's Georgia Hall finished in 12th place on two under.
Canada's Brooke Henderson came second, with Gaby Lopez of Mexico in third.
Hitting a three-over-par 75 in her final round, Korda ended the competition at Lake Nona Golf and Country Club on 10-under 278 after 72 holes and was tied with France's Celine Boutier.
The 23-year-old American led after the second and third rounds but failed to find her form on Sunday. Korda eventually drifted out the running following an early bogey on the fourth hole and a bogey on the 10th.
Although she regained a shot with a birdie on the 15th, back-to-back bogeys on the 16th and 17th saw her hopes quickly drop, along with her position on the leaderboard.
Korda's sister, Jessica, was seventh on eight under, while Hall's final-round 69 was not enough to see her break into the top 10. Compatriot Melissa Reid shot a 75 to finish on seven over.