A putting masterclass saw Mirim Lee take a three-stroke lead after the first round of the U.S. Women's Open.
Lee holed 10 birdies and dropped just two shots as she posted a dominant eight-under-par 64 in San Martin, California on Thursday.
The 25-year-old South Korean - seeking her first major LPGA tour title having fared no better than fourth at this year's Women's PGA Championship - opened with three birdies from her first four holes at CordeValle Golf Club.
Lee then picked up shots at the sixth, seventh and ninth holes before the turn, where she dropped the 10th but birdied the 11th, 12th, 16th and 18th.
Countrywoman Amy Yang, American Cristie Kerr and Australian Minjee Lee are tied for second.
Anna Nordqvist, Brittany Lang and Kelly Tan all posted opening-round 68's for a share of fourth position.
Nordqvist hit all 18 greens in regulation, the first time in the tournament's history, according to the United States Golf Association.
Ji Eun-hee, Moriya Jutanugarn and Sydnee Michaels are a stroke further back at four under, while Ariya Jutanugarn is in a 12-way tie for 11th spot, six shots adrift of Mirim Lee.