MIAMI (AFP) — South Korea’s Kim Sei-young birdied the 72nd hole to close out a one-stroke victory over Charley Hull Sunday and claim the record $1.5 million winner’s prize at the LPGA Tour Championship.

Kim, leader after each of the first three rounds, struggled to build momentum Sunday at Tiburon Golf Club in Naples, Florida.

She was one-under for the day through 17 and England’s Hull had joined her atop the leaderboard at 17-under par with a bogey-free six-under 66 that included birdies at 16, 17 and 18.

A playoff looked more than possible, but Kim didn’t blink, rolling in her fifth birdie of the day at the final hole to seal the win with a two-under par 70 for an 18-under par total of 270.

Hull, who started the day five off the pace, said she knew after birdies at the second, 12 and 13 that she had a shot at the largest winner’s cheque ever in women’s golf.

“Kind of 15 I looked at the leaderboard and I thought I’ve got a chance,” she said. “I didn’t birdie 15, but I birdied 16, 17, 18 — I gave it my best shot.”

Kim said that at 18, she hadn’t even realized that Hull had reached 17-under.

She was just trying to contain the nerves that had dogged her all day.

“I was really nervous when I was walking through the whole 18,” she said, adding that she “just tried to play like a practice round”.

Even more than the prize money, Kim said, she was delighted to achieve her pre-season goal of adding a third title of the year to a resume that now includes 10 victories.

American Danielle Kang delivered a storming seven-under final round, highlighted by an eagle at 17, to share third place on 272 with Nelly Korda.

Korda, who started the day two back and played in the final group with Kim, posted a one-under 71.