Choi, who started her day on the back nine at Highland Meadows Golf Club, rolled in birdies at the par-3 8th and par-4 9th holes to move to 7-under. Giving her a one-shot lead over Aditi Ashok of India and China’s Xiyu Lin.
One shot further back at 5-under 66 are South Africa’s Paula Reto and Thai players, Chanettee Wannasaen and Natthakritta Vongtaveelap.
Sarah Kemp is the leading Australian after posting a 3-under 69. The 38-year-old enjoyed a bogey-free round and made birdies on the 9th, 10th and 13th holes.
Sarah Kemp is firmly in contention after the opening round in Ohio. PHOTO: Getty Images.
Compatriots Sara Jane Smith, Grace Kim and Hira Naveed all shot 71 to be even par for the tournament.
Leader Choi kept a bogey-free card Thursday but did all her scoring over the final 11 holes after opening with seven pars in a row. She birdied 17, 18, 1 and 2 to kick into gear.
“It was really great day,” Choi said. “I mean, I start a little weird, like my shot was not really great, so I try just … make the par. Try to like until (her 7th hole) and then I make the birdie on 8, so I think, ‘Oh, I can do very better.'”
Choi is coming off a T7 finish at last week’s major in France, the Evian Championship.
Ashok, a five-time winner on the Ladies European Tour, is also in search of her first LPGA win. She posted three birdies on each nine without a bogey.
“I think I really like the golf course,” Ashok said. “It’s something similar to what I grew up on, tree-lined and smaller greens. That’s kind of how it was when I grew up back in India.
“Yeah, I had my first-ever top 10 on tour at this course (and) played well here last year. Yeah, good memories and I think that helps sometimes.”
Lin led the field with eight birdies but bogeyed the first hole of each side.
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