Sei Young Kim recorded a historic win in Wisconsin after becoming the first LPGA Tour player to go below 30-under par.
Going into the final day of the Thornberry Creek LPGA Classic, the South Korean already held an eight-shot lead and went on to close with a seven-under 65 round on Sunday, putting her on 31-under 257 overall.
After a blemish-free third round, the 25-year-old followed up with another faultless day, mixing 11 pars with seven birdies.
Across 72 holes, she fired a total of 31 birdies, one eagle and just one wayward double bogey on the par-three 17th on day two.
Speaking of her 63-65-64-65 tournament, surpassing Annika Sorenstam's 27-under record from 2001, she told LPGA.com: "After I shot 27-under (at the 2016 JJTBC Founders Cup), I wanted the 72-hole record. This is a dream come true."
The second-place finish went to Carlota Ciganda, who ended nine strokes adrift of Kim, while Anna Nordqvist, Emma Talley and Amy Yang tied for third.