Kirk and Choi finished with 68s but were still six off the pace after China's Liu fired an amazing 10-under 62 to break her personal best on the same course at Thornberry Creek.

The two Aussies are tied 32nd in the 140-player field, with almost half the field capitalising on the soft conditions to shoot scores in the 60s.

One year after the 23-year-old Liu shot her lowest round on the LPGA Tour there, she tied the course record to take a one-shot lead from Jeongeun Lee6 and Yealimi Noh, who only got into the tournament through Monday qualifying.

"I really like the golf course, apparently," Liu said. "So it's just nice to be out here. Just great vibes."

Sung Hyun Park, who won last week in Arkansas to return to No.1 in the world, opened with a 65.

RIGHT: Liu tied the course record at Thornberry Creek and leads by one shot after the opening round. PHOTO: Stacy Revere/Getty Images.

Liu started on No.10 and shot a 30 on the back nine, including an eagle on the par-5 13th hole. She thought her score could have been lower, especially after failing to birdie two of the par-5s, including her last hole at No.9.

Even so, she did what was required on a course that felt like target practice.

"It was playing pretty soft, so it takes a lot of the pressure off for the approach shots because you know where you land is pretty much where you're going to finish," Liu said.

"So not much calculation was needed. I was just hitting it pretty solid."

Tiffany Joh and Nasa Hataoka are among those at 64, while the group two shots behind at 65 includes Park, Shanshan Feng and Anna Nordqvist, who last year shot 67 in all four rounds for 20 under and still finished 11 shots behind.

"This is just a course that for some reason you know you have to make birdies," Nordqvist said.

"So I just try to keep making birdies and keep staying aggressive."