SAN DIEGO (AP) - Na Yeon Choi of South Korea shot a career best 9-under 63 to take a two-stroke lead over compatriot Jiyai Shin in the Samsung World Championship at Torrey Pines on Saturday.
"I had a great round today," Choi said. "I felt almost perfect with everything. My driver was good, iron shots good, and wedge and putter good. I think it was perfect today."
Choi finished at 15-under 201 to tie the tournament's three-round record set by Annika Sorenstam when the Swede won here in 2002 and 2005. Choi began the day three strokes behind second-round leader Shin, who shot a 68.
Choi has never won on the U.S. LPGA Tour, but has eight top-10 finishes this year, including a tie for ninth at the U.S. Women's Open.
After yielding 14 rounds in the 60s in the first two days, Torrey Pines was toughened up with faster greens and tighter pin placements on Saturday. Only Ai Miyazato of Japan (68), Shin and Choi shot 60s. Shin and Miyazato, who played together, were amazed by Choi's score.
"That's a really solid round," Miyazato said. "Nine under, that feels like 12-under on a normal golf course. This is not a very easy golf course."
Miyazato was three strokes back in third after her third straight 68. No. 1-ranked Lorena Ochoa of Mexico shot a 72 and was tied for fourth place with Paula Creamer, seven strokes back.
After making the turn at 30, Choi had birdies on Nos. 11-12 to get to 8 under and have a chance at a 59, the U.S. LPGA Tour record Sorenstam set in 2001 at the Standard Register PING.
"I didn't think about that," Choi said. "Actually I didn't know that until after the 12th hole when I made a birdie. I just try to reach the hole." She stalled after that, making two pars and a bogey on the 419-yard, par-4 15th. Her approach was about 45 feet from the hole and she left her first putt 9 feet short then failed to convert the par attempt. Choi rebounded with birdies on two of her final three holes.
"I think actually I was nervous today, but I'm just trying to talk more with the caddie and just keep trusting myself," she said. "Be more aggressive and more confident. Actually, I feel like I have no lows, so I'm just trying everything."
Though Shin and Choi entered the tour about the same time, Shin has won three times while Choi is going for her first victory.
"I think that's a big thing," Shin said. "I've played a lot with Na Yeon Choi in Korea and also the LPGA Tour. Because she's never won on the LPGA Tour maybe she'll get more pressured and nervous." Shin kept the lead until she stumbled on the back nine, bogeying two of the first three holes.
"I am nervous and feel pressure too," Shin said, "but I really like feeling the adrenaline."
That will come in handy on Sunday.