Chun In-gee birdied three of the last four holes in her first appearance at the US Women’s Open to win by one stroke in only her eighth LPGA event.
The 20-year-old South Korean, the world No.20 and leading money winner on the South Korean tour, fired a final round four-under par 66 to win a back-nine shootout for her first major title after 15th-ranked compatriot Amy Yang took a bogey on the final hole.
Chun birdied the 15th to seize the lead at Lancaster Country Club followed by the 16th and 17th to stay on top, but bogeyed the 18th to open the door for Yang, who eagled 16 and birdied 17 but missed her chance with a bogey at 18.
Australian veteran Karrie Webb, who was the co-tournament leader after the first round, finished in a tie for 14th, after shooting even par for the tournament.
“It was my first time playing the US Women’s Open so I tried to enjoy the game in every moment,” Chun said through a translator.
“It was great. I tried to have fun. Every moment was new.”
Chun finished on eight-under 272, while Yang was second after a closing 71. World No.1 Park In-bee of South Korea and American Stacy Lewis shared third on 275.
“Right off the first tee, you could feel the energy,” Lewis said.
“You had to fight your way through it.”
Canadian teen Brooke Henderson shared fifth on 277 in a pack with Sweden’s Pernilla Lindberg, Japan’s Shiho Oyama, South Korean Ryu So-yeon and Americans Morgan Pressel and Jane Park.
Chun is the third-youngest winner in US Women’s Open history after Park, who won in 2008 at age 19, and Pak Se-ri, who was 20 when she won the 1998 crown.
She is also the first player to win the event in her debut since compatriot Birdie Kim a decade ago.
Yang missed out on her first major title after topping the leaderboard for the second year in a row. She was in the final pairing on Sunday for the fourth time in five years, but it was Chun who became the sixth South Korean winner in eight years at the event.
Yang led Chun by two at the turn and three after Chun made bogey at 10.
But Yang missed the green with her approach at 11 and took a bogey, while Chun birdied 12 to pull within one and Lewis birdied 13 to join her on six-under.
When Yang took a bogey at 14, she fell into a three-way tie for the lead with Chun and Lewis.
Chun jumped into the lead at seven-under with a six-foot birdie putt at 15, only the third birdie of the day at the hole, while Yang followed with a bogey at 15 and Lewis fell two back with a double bogey at 15.
It would be too much for Yang to make up.