SYLVANIA, Ohio (AP) — Gerina Piller shot an 8-under 63 on Thursday in the Marathon Classic to take a one-stroke lead over U.S. Women's Open champion Sung Hyun Park and Peiyun Chien.

Winless on the LPGA Tour, Piller had nine birdies and a bogey in the first round at Highland Meadows. The American birdied four of the first five holes and four of the last eight.

Park, the South Korean player who won her first major title last week at Trump National in New Jersey, had seven birdies in a bogey-free round. Chien, a LPGA Tour rookie from Taiwan, had eight birdies and a bogey.

Kelly Shon, Aditi Ashok and In-Kyung Kim shot 65, Angel Yin and Sandra Changkija followed at 66, and U.S. Solheim Cup players Lexi Thompson, Brittany Lincicome and Alison Lee topped the group at 67.

Stacy Lewis, her U.S. Women's Open chances ruined by a third-round meltdown, had a 69.

Canadian Brooke Henderson shot 70.

Lydia Ko, winless since her victory last year at Highland Meadows, had a 73. She had three bogeys and one birdie.

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