Sweden's Annika Sorenstam lost her last chance to win an LPGA event this year and US teen Morgan Pressel served notice she will contend for the title on Friday at the LPGA Tour Championship.
Pressel fired a seven-under par 65 to grab a share of second after 36 holes at the season-ending LPGA showdown for a US$1 million top prize, but the scores are erased as the top 16 players enter the third round.
The top eight finishers in yesterday's third round will advance to today's final round for an 18-hole showdown for the top prize, 10 times what the runner-up will earn at the US$1.55 million event.
Kim fired a 70 to hold off Pressel and stand on seven-under par 137 after 36 holes, even though it only meant she was the leading qualifier for the weekend with Pressel and fellow American Christina Kim sharing second on 138.
Kim, who shared the lead with US veteran Kim when the day began, birdied the sixth hole, took a bogey at seven but birdied the par-5 12th and par-4 14th, then parred her way in to remain in front.
"I'm thinking about people that are in eighth place right now, I have to beat them, which is only like three strokes or something like that," she said. "I just want to make it to Sunday. Whatever happens happens."
Pressel birdied the third, fourth and sixth and then began the back nine with three birdies in a row. Her lone bogey of the day came at the par-4 13th but she answered with back-to-back birdies and closed with three pars.
"Everything just kind of jelled," Pressel said. "I hit the ball really solid and I gave myself plenty of birdie opportunities and I putted better than I can ever remember putting, so that's kind of nice."
World No. 1 Lorena Ochoa of Mexico, who has already clinched the season money title, fired her second 70 in a row to stand with American Cristie Kerr on 140, a stroke ahead of Norway's Suzann Pettersen and American Paula Creamer.
Also advancing to the weekend were Sweden's Sophie Gustafsson, Americans Nicole Castrale, Julie Inkster and Natalie Gulbis, Koreans Seon Hwa Lee and Sarah Lee, Britain's Catriona Matthews, Australian Karrie Webb Japan's Ai Miyazato.
Gulbis, Miyazato and Annika Sorenstam were level for the last two spots on 147 but former world number one Sorenstam lost out in a two-hole sudden death playoff for the final two spots in the weekend.