Steph Kyriacou has fallen short in her bid for a first LPGA Tour title despite a brilliant final round as Thailand's Jeeno Thitikul closed with a three-under 69 for a four-shot victory over Celine Boutier in the Mizuho Americas Open.

Thitikul, who captured the Race to CME Globe and its $4 million prize to end last season, played bogey-free over the final 27 holes at Liberty National over the weekend to win for the first time this year and the fifth time in her LPGA Tour career.

Kyriacou had to settle for a tie for fifth after shooting a five-under 67, featuring seven birdies, which proved the best round of the day by anyone.

Nelly Korda is still trying to win for the first time this year. She was within one shot of Thitikul until driving into the hazard on the par-four ninth and taking bogey.

It was a downward spiral from there, as Korda played the back nine with two bogeys and no birdies and was never a factor the rest of the way.

The final challenge came from Boutier, who was posed to catch the Thai player on the 15th hole when she hit her approach to 10 feet.

Thitikul faced a tough par save from a bunker left of the green, with her foot up against the slope and having to clear another bunker to a back pin.

Thitikul pulled off the shot perfectly to three feet to save par. Boutier not only missed her birdie chance, she missed the 30-inch comeback putt and made bogey.

So, instead of a two-shot swing and a tie for the lead, Boutier fell three back with three holes to play.

On the 16th, Boutier missed an eight-foot birdie putt and Thitikul made her par putt from seven feet to stay three shots behind. Thitikul all but ended the tournament with a 10-foot birdie putt on the 17th hole, and she capped off a clean par with a par save on the 18th.

"I know that a lot of putts didn't drop on the front nine, but I'm trying to do my best," Thitikul said. "I was just trying to tell myself, 'Be patient, it's coming, it's coming.' That's pretty much what I told myself today."

Thitikul finished at 17-under 271, while Boutier shot 72 to finish second, followed by Carlota Ciganda (70) and Andrea Lee (72), with Kyriacou level in fifth with Korda (73) and Yealimi Noh (72).