Nelly Korda hit a bogey-free seven-under-par 65 to claim her third LPGA Tour victory on the trot in Arizona.
The world number one, who started the day two shots off the lead, closed with two birdies in her final three holes to set the clubhouse target on 20 under.
Australian rookie Hira Naveed (66) finished second on 18 under, while Lexi Thompson’s challenge ended in the water on the 16th as she faded to third.
“I knew I had to shoot a low one and I played some smart golf,” said Korda.
“It’s hard mentally to stay 100% the week after a win but to win three on the trot is a dream.”
Korda won the LPGA Drive On Championship in January and then took seven weeks off before returning to win last week’s Seri Pak Championship in California. This week’s win at the inaugural Ford Championship in Phoenix is her 11th Tour title.
She is the first player to win three LPGA Tour events in succession since Thailand’s Ariya Jutanugarn in 2018. American Nancy Lopez (1978) and Sweden’s Annika Sorenstam (2004-05) hold the record with five.
European Solheim Cup players Carlota Ciganda of Spain and Sweden’s Maya Stark both finished joint third on 17 under in blustery and rainy conditions.