ONEIDA, Wis. -- Sei Young Kim watched her 12-foot birdie putt break toward the hole and disappear into the cup, putting her in territory no one had ever been on the LPGA Tour.
She reached 30-under par in the Thornberry Creek LPGA Classic.
And she wasn't finished.
Kim added yet another birdie, closed with a 7-under 65 and wound up her historic week Sunday in Wisconsin at 31 under for a nine-shot victory.
"I never thought I'd shoot 31 under," Kim said. "I really feel incredible."
She was every bit of that in a week so dominant that she now has two LPGA scoring records all to herself.
Kim's 31 under broke by four shots to par the record she had shared with Annika Sorenstam. Kim won the 2016 Founders Cup at 27 under, while Sorenstam won the 2001 Standard Register Ping at 27 under, the tournament where the Swede shot 59.
"After the Founders Cup, I got new goals," she said. "I wish I could break up the [tour] record. It's really unbelievable."
Kim also set the 72-hole scoring record at 257, finishing with three straight pars to break the mark by one shot.
The 25-year-old from South Korea opened with a 63, followed with a 65 and shot a 64 on Saturday to reach 24 under, which tied Sorenstam's 54-hole record in 2003 at the Mizuno Classic in Japan, a 54-hole event.
"In a word, phenomenal," said defending champion Katherine Kirk, who finished 15 under and tied for 20th. "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 going to break our all-time, 72-hole scoring record pretty easily. She's a great player. She obviously knows how to win. She just kept the foot down."
The only blemish for Kim all week at Thornberry Creek at Oneida was a double bogey in the second round Friday. She had 31 birdies and one eagle, another record for most sub-par holes in a tournament. Kim hit 67 out of 72 greens in regulation.
For all the birdies, Kim set the LPGA Tour record with a par on the final hole to finish at 257. Hee Young Park won a playoff after she and Angela Stanford each finished at 258 in the Manulife Classic in Canada in 2013 (par 71), while Karen Stupples shot 258 at the Welch's/Fry's Championship in Arizona in 2004 (par 70).
"I had the double-bogey on 17. That was the only one I had where I missed the shot. It's crazy," Kim said.
She reached 28 under with a tap-in birdie on the par-5 ninth. Kim began the back nine with another birdie when her wedge from about 100 yards stopped a few feet from the hole, setting up her birdie on the 12th.
Kim won by five over Lydia Ko when she shot 27 under in the Founders Cup two years ago. Sorenstam won by two over Se Ri Pak when she shot her 27 under at Moon Valley at a tournament that no longer exists.
No one had a chance Sunday.
Kim began the final round with an eight-shot lead and was close to flawless. Amy Yang, who played with Kim in the final round, made eagle on No. 3 to get within six shots. She couldn't keep pace, however, and made a double bogey on the par-5 15th by hitting one shot in the water and another in a hazard..
Carlota Ciganda of Spain lost a ball and made double bogey on the 18th hole for a 64 to finish alone in second, nine shots behind. Yang, with a birdie on the final hole for a 68, tied for third at 20 under with Emma Talley and Anna Nordqvist, who each had a 67.
"I was thinking even not playing this tournament, going home and rest, so I'm happy the way I played," Ciganda said. "Lots of birdies; lots of good shots. Today my putting was very good, so very happy with the way I played."
Kim won for the first time this year and joined Brooke Henderson as the only players on the LPGA Tour with at least one victory in each of the past four seasons.