Thailand's Pornanong Phatlum claimed the Omega Dubai Ladies Masters title in brilliant fashion on Saturday, edging out world number three Stacy Lewis in a final-round duel.
British Open winner Lewis began the day with a two-shot lead and led by three when she birdied the second, third, eighth and 10th to improve to 15-under-par.
Phatlum reduced the gap with birdies on the 13th and 14th but Lewis looked to have struck a decisive blow when she hit her approach to the 17th to five feet.
However, Phatlum's second shot was even better and after Lewis had missed, the 24-year-old holed for birdie to draw level before an even better approach to the par-five 18th left her a tap-in birdie to complete a superb 66 and seal victory.
Lewis had missed from long range to force a play-off and had to settle for a closing 69, with Spain's Carlota Ciganda a distant third, seven shots adrift.
English teenager Charley Hull finished in a tie for eighth place to secure rookie of the year honours on the Ladies European Tour.
"I am very excited. I just played my own game and stayed calm under pressure," Phatlum said. "I have learned how to stay focused through meditation which I practice with my brother, who caddies for me.
"When I'm on the course I just play my game and I didn't think about the win. I don't want to pressure myself."
Lewis said: "I'm disappointed. The back nine that Pornanong played was pretty impressive. She hit golf shots when she needed to and made the putts and I didn't. It's been a really good year. It's had its highs and lows. I've played some really consistent golf."