Thailand's Patty Tavatanakit shrugged off an erratic start to take a one-shot lead into the final round of the $1.6 million Honda LPGA Thailand after carding a two-under-par 70 on Saturday.

Three strokes clear at the start of the day at Siam Country Club, Patty's advantage was cut after she recorded two bogeys on the front nine.

But the 21-year-old ANA Inspiration winner dug deep, firing birdies at the 14th, 15th and 18th holes to move to 18 under for the tournament, one shot clear of Germany's Caroline Masson and compatriot Atthaya Thitikul.

"Not every day is perfect," Patty said. "Even though I had some nice rounds, it was still not perfect, which is I feel like it's the nature of the game itself.

"I'm really proud of myself of how I hung in there and grinded back to shooting under par."

Atthaya, bidding for her maiden LPGA Tour title, bogeyed the first and third holes before collecting four birdies in the last seven holes for a 68.

Mexico's Gaby Lopez and New Zealand's Lydia Ko produced identical rounds of 67 to remain in a share of fourth place, while Hannah Green surged up the leaderboard to sixth spot after firing eight birdies in a flawless round of 64.