Ariya Jutanugarn became the first Thai winner in LPGA Tour history after victory in the Yokohama Tire LPGA Classic on Sunday.
Jutanugarn held off Amy Yang, Morgan Pressel and Stacy Lewis by a stroke despite losing two shots off her third-round lead in Alabama.
The 20-year-old sank a clutch four-foot par putt for her first LPGA victory, carding 72 to finish at 14-under-par 274.
"So tough, I feel the three holes I can't control anything," said Jutanugarn. "My legs were shaking, my hands were shaking."
"Thank you for my mom for being with me all the time to support me and happy Mother's Day."
Jutanugarn looked nervous down the stretch, hoping not to repeat the bogey, bogey, bogey finish at the ANA Inspiration last month.
However, she finished with four birdies and three bogeys a day after tying the tournament record with a 63.
Yang (67) put in an impressive final-round performance but a bogey on the 17th cost her in the end.
Lewis (68), winner in 2012, and Pressel (68) also tied with Yang for second at 13 under, with Caroline Hedwall (68) finishing one stroke behind in fifth.