Sei Young Kim has become the first player in LPGA Tour history to go lower than 30-under-par, on her way to a nine-shot win at the Thornberry Creek LPGA Classic on Sunday.
The 25-year-old South Korean smashed the previous record she shared with Annika Sorenstam for the highest accumulative total by four shots.
Kim closed with a seven-under 65, leaving her at 31-under 257 for the tournament, for a dominant victory over Spain's Carlota Ciganda. Anna Nordqvist, Amy Yang and Emma Talley finished joint third, 11 behind Kim.
"I never thought I'd shoot 31-under," Kim said. "I really feel incredible."
The previous LPGA 72-hole record was 27 under par, set by Annika Sorenstam at the 2001 Standard Register Ping and tied by Kim at the 2016 JTBC Founders Cup.
With Kim entering the final round holding an eight-shot lead, the only question was whether she would continue to tear up Thornberry Creek's Legends Championship Course to overtake Sorenstam's record.
That proved to be no challenge to Kim, who birdied the 1st hole and cruised home with a bogey-free round. For the tournament, she never recorded a bogey, with her only blemish being a double bogey at No.17 on Friday.
Kim wound up with 31 birdies and one eagle, on the 3rd hole Saturday. The 32 holes under par is another record, breaking the mark of 30 set by Brittany Lincicome, Gerina Pillar and Lexi Thompson at the 2017 Pure Silk-Bahamas LPGA Classic.
She hit 43 of 56 fairways and 67 of 72 greens in regulation. Kim required just 115 putts over the 72 holes.
The win was the seventh of Kim's LPGA career, her first since she captured the Citibanamex Lorena Ochoa Match Play in May 2017. She has yet to win a major title.
The Thornberry winner's cheque of US$300,000 pushed Kim's career earnings past US$5 million, making her the 61st player to reach that plateau in LPGA history.
Kim and Brooke Henderson are the only players to have registered LPGA wins in 2015, 2016, 2017 and 2018.
Katherine Kirk, who shot 62 on Thursday to lead after the first round, finished at 15-under in a tie for 20th, a shot better than compatriot Minjee Lee.
"In a word, phenomenal," Kirk said of Kim's performance.
"We knew that you could go low around this golf course, but she's taken it to a whole other level. It's pretty exciting to watch, really.
"She's a great player. She obviously knows how to win. She just kept the foot down."