Patty Tavatanakit shot a 66 on Saturday at the Honda LPGA Thailand to take a three-shot lead into the final round at the Siam Country Club Old Course in Chonburi.
She is aiming to become the second Thai player to win the home-country tournament since it began in 2006.
Standing at 16-under after three rounds, Tavatanakit gained some separation from the field, thanks to a round that saw her sink four birdie putts and add an eagle in the first seven holes. Her co-leader after 36 holes, Madelene Sagstrom of Sweden, shot a 69 to come in at 13-under and is in second place.
Another shot back and in a tie for third are Norway's Emily Kristine Pedersen (65 on Saturday) and a pair of South Koreans, Hye-Jin Choi (65) and Hyo Joo Kim (69).
Five women are in a logjam at 11-under and tied for sixth place -- amateur Suvichaya Vinijchaitham and Ariya Jutunugarn of Thailand, Canada's Brooke Henderson, Albane Valenzuela of Switzerland and Sei Young Kim of South Korea.
On another sizzling day in Choburi, the players had to fight through 90-degree temperatures.
"I'm really proud of my performance today," said Tavatanakit, who is aiming for her second LPGA Tour career win. "It's getting very tiring, exhausting in the heat. I'm just going to conserve my energy and take on the challenge tomorrow."
She is looking for consecutive wins after her victory last week at the Aramco Saudi Ladies International on the Ladies European Tour.
"Feel like last week gave me a lot of confidence going into tomorrow. I'm not saying I'm going to guarantee the result right away, but there is a lot of positives and a lot of good things to look at the past seven rounds I've played," she said. "So I'm just going to have fun, stay present, and be very, very busy with my process."
Sagstrom gained momentum and confidence on the final hole Saturday with an eagle to cap a round that also included three birdies and two bogeys.
"Patty is playing beautifully. She is hitting the ball lovely and she is putting even better. She left a few putts short today and she could have gone really low today, Sagstrom said.
But she is not counting herself out.
"I think you kind of know that to really have a chance for tomorrow you have to play good golf. You don't really do that by comparing yourself to somebody else or trying to react on their games. All I need to do is get my own zone and out of my own way," Sagstrom said.
She has one tour win, earned in 2020.
Pedersen, who tied Choi for the day's low round on Saturday, is looking for another stellar round on Sunday.
"I want to keep the foot on the gas. I played with [Tavatanakit] on Sunday in that final round in Saudi and she just played unbelievable that day," said Pedersen, who finished tied for sixth last week. "But I do believe I can play like that myself and hopefully I can do that tomorrow."
Defending champion Lilia Vu turned in her second straight 67 after an opening-round 73 to move to 9-under for the tournament.
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