Late surges from Stacy Lewis and defending champion Kim Sei-young were not enough to usurp Kim Hyo-joo, who prevailed by two shots in the Pure Silk Bahamas LPGA Classic.
South Korea's Kim Hyo-joo carded a seven-under 66 to finish 18-under for the tournament, while rounds of 68 for Lewis and compatriot Kim Sei-young saw them fall short.
The trio had been tied for third after round three, one shot behind the leading duo of Anna Nordqvist and Charley Hull.
Nordqvist and Hull failed to build on their strong positions, although the Swede - out of realistic contention heading down the 18th - ended in a tie for second with a birdie completing her round of 69.
Hull, meanwhile, singed for a 71 to drop back to a tie for eighth, two shots further adrift.
At one stage, Kim Hyo-joo seemed destined for a comfortable victory as she pulled three shots clear with four to play, but Lewis had other ideas.
The American picked up three successive birdies between the 13th and 15th holes, while a bogey for Kim Hyo-joo on the 16th saw her advantage cut to just one.
She regained her composure immediately to birdie the 17th and although Kim Sei-young picked up a shot at the last, neither she nor Lewis could prevent Kim Hyo-joo from claiming the title.