Thailand's Chanettee Wannasaen managed a birdie-eagle finish to grab a one-stroke lead after Friday's second round of the LPGA Dana Open.
Chanettee fired a six-under par 65 to stand on 11-under 131 after 36 holes at Highland Meadows in Sylvania, Ohio.
That was enough to lift her ahead of defending champion Linn Grant of Sweden and China's Lin Xiyu with China's Mary Liu fourth on 133.
Chanettee, ranked 43rd, won her only LPGA title at last September's Portland Classic as a Monday qualifier.
This year, she was third at the Americas Open in May and shared eighth at last month's Dow Championship.
"Actually I'm really nervous right now, so I think on the weekend I will do my best," she said. "I don't want to like get stressed for the weekend."
The 20-year-old Thai standout birdied the par-3 second hole and answered her lone bogey at four with a birdie at the par-3 eighth.
After birdies at the 11th and par-3 14th, Chanettee closed with a birdie at 17 and eagled the last to grab the lead.
"The back nine I played really good," Chanettee said. "The putter was really good on the back nine."
Grant birdied five of the first seven holes and sank a 10-foot birdie putt at the 17th on her way to a 65 in her last tuneup for the Paris Olympics.
"I really had some good game going and hit some great shots," Grant said. "Felt like I could really go out and be aggressive. I feel like my game is really good."
HIGHEST RANK
Lin, the highest-ranked player in the field at 15 in the world, seeks her first LPGA crown in her last Olympic tuneup.
Lin birdied three of the last four holes on the front nine, followed her lone bogey at 11 with a birdie at 12 and closed with a birdie to shoot 67 and match Grant for second.
"This course overall, it really suits my eyes and it's all about putting for me," Lin said. "I just need to get on the fairway and be smart and then I'll have plenty of opportunity."
Sharing fifth on 135 were South Korea's Ryu Hae-ran and Choi Hye-jin, South African Paula Reto, Japan's Mao Saigo and Australian Sarah Kemp.