Kristy McPherson is alone atop of the leaderboard at the Kraft Nabisco Championship at Mission Hills after shooting a two-under 70 move on to eight-under 208 overall.
On a day when nobody ran off with the lead, McPherson at least moved into the sole lead by opening the back nine with three straight birdies to put herself one shot ahead of Christie Kerr, who also went round in 70.
The 27-year-old McPherson shared the lead with Christina Kim at the start of the day, but her rival Kim faltered in the third round with a 75 to end up five shots back.
Brittany Lincicome, whose 66 topped the first round, also shot a 70 to remain in contention, two strokes behind McPherson.
Defending champion Lorena Ochoa holed a birdie on 18 to finish on an even 73 - her best round of the tournament. She was tied for 15th at two over.
At the bottom of the leaderboard, Michelle Wie had another bad day with her second straight nine-over 81. She was at 17 over for three rounds.
She endured a torrid round of three double bogeys, four bogeys and only one birdie.