Already playing through a back injury that forced her to alter her swing, the 26-year-old South Korean overcame a rough start Sunday in cold and windy conditions, then fended off Bronte Law and Jeongeun Lee6 with a birdie on the first extra hole. She won for the eighth time on the LPGA Tour, improving to 4-0 in playoffs.
"I think that this win very hardest to win in my life, ever," Kim said. "Last seven wins, I played really well final round. But today I wasn't good final round. So I think that playing style, little tough to win. It means a lot."
Three strokes ahead entering the day, Kim opened with a double bogey and a bogey and dropped another stroke on No. 8. She birdied the par-5 15th to regain a share of the lead, dropped back with a bogey on the par-3 17th and birdied the par-5 18th for a 3-over 75 and a spot in the playoff at 7-under 281.
"Even tough pin position, I try to go to the aggressive strategy," Kim said. "But that strategy make the first hole and the second hole, third holes like no good result. After that I changed the strategy. If the pin position easy, going to the aggressive. If not, just avoid the pin, stay stable."
Law closed with a 65, finishing about 2 1/2 hours before Kim, and Lee6 had a 67. Kim nearly retraced her regulation path on the 18th in the playoff, almost driving into her own divot and hitting another 4-iron from 199 yards a foot closer than before onto the front right fringe.
Law left her approach short and right and pitched to 6 feet. Lee6's approach bounced into the middle of the green, leaving her a 40-foot eagle putt that she hit 6 feet past. After Kim putted to 2 feet, Law missed her birdie putt to the right, and Lee6's try went left. Kim then ended it.
She won for fifth straight year and first since shooting 31-under 257 last summer in the Thornberry Creek LPGA Classic in Wisconsin to break the LPGA Tour record of 27-under 261 she shared with Annika Sorenstam.
"Totally different," Kim said. "When I shoot the 31 under and I look at the hole, just every hole in. But today, it wasn't. Most hole like miss the hole." Law, the 24-year-old former UCLA star from England, missed a chance to tie the LPGA Tour record for the largest comeback at 10 strokes.
"Obviously, the greens are quite bumpy right now, it makes it kind of difficult at the end," Law said. "Thought I hit a good putt there, so it didn't go in. It happens." She made five birdies in a six-hole stretch in the middle of the round and reached 7 under with a 4-wood to 4 feet for eagle on No. 15. She parred the last three, canceled her scheduled flight and waited to see if she'd win or get into a playoff.
"Ultimately, waiting around that long is tough, to even get back into the mindset of, like, 'OK, I got to go out and play again,'" Law said. "But that's part of the job." Lee6 played the final four holes in regulation in 4 under, holing a 12-footer for eagle on 15 and making birdies on 16 and 18.
"Not really happy with the three putts," Lee6 said through a translator. The 22-year-old South Korean has the number in her name because she was the sixth player with the name on the Korean LPGA. She has embraced the number, answering to it and writing a large "6'' on her balls. Her South Korean fan club is called "Lucky 6." Jeongeun Lee5 also plays the LPGA Tour.
Lexi Thompson, Amy Yang, Eun-Hee Jiand Charley Hull tied for fourth at 5 under. Thompson, Yang and Ji each shot 71, and Hull had a 74. Hull eagled the 15th to get within a stroke of the lead, then bogeyed the 16th and parred the final two.