Hsu Wei-Ling struck early with five birdies in a five-under par 66 on Thursday to take a two-shot lead in the LPGA Pure Silk Championship in Williamsburg, Virginia.
Hsu's five birdies included three in a row at the 12th, 13th and 14th on the Kingsmill Resort course, where South Korean world No. 3 Kim Sei-young headlined a group of five players sharing second on 67.
Kim was joined by China's Liu Ruixin, Spain's Luna Sobron Galmes, Malaysia's Kelly Tan and South Korean Jeon Ji-won..
It was a further stroke back to an all-American quintet on 68: Elizabeth Szokol, Tiffany Joh, Ryann O'Toole, Megan Khang and Stacy Lewis.
"Actually I feel quite the same from (the) very first hole all the way to the 18th," said Hsu, who hit 13 of 14 fairways in regulation and 14 of 18 greens.
"I just kept waiting," she said. "(I had) a lot of birdie chances. I just kept waiting, and finally when I made the turn, three birdies in a row on the back nine on holes 12, 13, 14."
Hsu said she hadn't gone into the round with high expectations.
"I've only slept I will say 20 hours in the last five days," she said, after coping with the trip from the LPGA Thailand to Williamsburg.
Along the way she played a 36-hole qualifier in Arizona for the US Women's Open in Arizona -- where she actually ended up playing 37 holes, making a birdie on the first extra hole to earn the alternate spot for the women's major in San Francisco.
Kim had five birdies for her share of second place while Liu had six birdies in her four-under effort.
Liu, still trying to make the permanent leap from the Symetra Tour developmental circuit, teed off on 10 and had four birdies through nine holes. She was slowed by bogeys at the second and sixth but finished with back-to-back birdies.
"The two bogeys were actually my swing issue, pulled them a little bit," Liu said. "I was able to fix my swing in the middle of the round to get everything straightened out."
She said two Symetra Tour wins this season had boosted her confidence.
"I know I can play well out here," she said.
Jane Park provided the shot of the day, a hole-in-one at the par-three fifth hole on the way to a three-over par 74.
"I actually hit the perfect shot," she said of her eight-iron from 148 yards. "People by the green said it rolled in just like a putt."