Inbee Park fired a 5-under 67 on Friday to move into first place at the Kraft Nabisco Championship.
Park, who is seeking her second career major title, finished 36 holes at Mission Hills Country Club at 7-under-par 137, which is a stroke ahead of Lizette Salas.
Salas carded a 4-under 68 during her second round to sit alone in second place at 6-under-par 138, while Caroline Hedwall (68) and Giulia Sergas (69) share third at 5-under.
Hee Young Park (70), Pornanong Phatlum (69) and first-round co-leader Jodi Ewart Shadoff (72) occupied fifth at minus-4.
Inbee Park started the day two shots off the pace of first-round co-leaders Ewart Shadoff, Na Yeon Choi and Suzann Pettersen, but quickly started to make her move up the leaderboard with a pair of birdies at the third and fifth.
After parring the next three holes, she birdied the ninth to grab sole possession of first place at 5-under.
The fourth-ranked player in the world then pulled further ahead of the pack with a streak of three straight birdies from the 11th before dropping a shot with a bogey at the 14th.
She closed her round with four straight pars to hang on to the lead.
"Obviously putted really good out there, and especially on the back nine. The wind picked up so it was tough out there on the back nine." said Park. "I played this golf course about eight years in my career and never really had a chance on the weekend, so I'm happy to be in the mix."
Salas traded a birdie at the first with a bogey at the fourth before hitting the turn at 3-under for the tournament with a birdie at the seventh.
She then made her push during her inward nine with a stretch of three birdies in a five-hole span from the 11th, which she capped with back-to-back birdies at the 14th and 15th to get within a stroke of Park.
Salas would get no closer, however, as she closed with three straight pars to remain in second place.
"It's something that I've kind of trained my mind in the last six months, playing solid golf and being in contention last week and the week before, so I'm just trying to get used to it as fast as I can," Salas said about being in contention for her first major victory.
Ewart Shadoff was the lone member of the first-round co-leaders to not drop a shot during her second round with her even-par 72.
Yeon Choi countered three birdies with four bogeys and a double bogey, while Pettersen recorded four bogeys and a birdie as each player carded a 3-over 75 on Friday.
NOTES: Park's lone major victory came at the 2008 Women's U.S. Open ... Defending champion Sun Young Yoo carded a 4-over 76 on Friday and missed the cut with a two-day total of 9-over-par 153 ... The cut line was set at 5-over- par 149, with 73 players advancing to the weekend ... Jeong Jang withdrew before her round on Friday and Eun Jung Yi withdrew after playing nine holes of her second round.