Ayako Uehara of Japan birdied seven of her final 10 holes and shot a 9-under-par 62 to take the first-round lead on Friday at the Walmart NW Arkansas Championship in Rogers, Ark.
Uehara, who made nine birdies and no bogeys, matched the tournament's 18-hole scoring record and was two strokes ahead of Candie Kung (64) in the LPGA event at Pinnacle Country Club.
Jane Park and Angela Park established the record in 2008. Uehara bettered the low round of her career, a 63 in Malaysia in 2014.
Uehara is ranked No. 215 in the Rolex World Ranking and has never won on the LPGA Tour. Her best finish is a third place at the 2012 Japan Classic.
"With the caddie and the trainer, everybody is like teamwork, and then that's my motivation now, and so everything is coming together, including the swing coach," Uehara said.
Kung opened with three straight birdies and added five more before her only bogey of the round at No. 6, her 15th hole of the day.
"I was having a lot of fun, and we had a good group of people that I like, and we all played very fast, so I think that helps, too, and we didn't wait at all the whole round, so I think that helps, too," Kung said.
A large contingent at 6 under included Angela Stanford, Vicky Hurst, Jing Yan, Alena Sharp, Sun Young Yoo, Chella Choi, Minjee Lee, Carlota Ciganda, Ai Miyazato, So Yeon Ryu, P.K. Kongkraphan and Morgan Pressel.
Top-ranked Lydia Ko posted a 66 and Stacy Lewis, a former world No. 1 who played college golf at nearby Arkansas, shot a 67. Second-ranked Brooke Henderson began with a 69.
For Pressel, it was her lowest score this year.
"I hit my wedges very well today," she said. "I certainly got off to a good start on 1 and 10 and 11. I think I really only made -- I'm trying to remember -- one birdie putt over maybe six or seven feet for the most part. I hit it pretty close all day and gave myself a lot of opportunities."
Defending champion Na Yeon Choi opened with a 75.