Second-round leader Lorena Ochoa managed an even-par 72. She is alone in second place at 8-under-par 208. Becky Morgan, who led after the first round, claimed third at minus-7 after a 71.
Creamer stumbled out of the gate with a three-putt bogey on the second that dropped her to minus-4. She came right back with a chip-in birdie at the next though. The Californian made it two straight as her 40-foot birdie putt on the fourth found the bottom of the cup.
The 18-year-old parred her next four holes before sinking a birdie on the ninth. Creamer cruised through the back nine with five consecutive pars around the turn at Locust Hill Country Club.
Creamer got within one of Ochoa with a birdie on 15. She took the lead at minus-9 with a 4-foot birdie putt on the 16th, after Ochoa bogeyed 15 behind her. Creamer made it three straight as her 5-foot birdie putt at 17 fell into the cup.
Ochoa clung to the lead most of the round despite opening with bogey on the second. She also rebounded with a birdie on the third.
The Mexican moved to minus-9 with birdie on the par-4 sixth. Ochoa reeled off eight straight pars around the turn. She stumbled to a bogey on 15 to fall out of the lead.
Ochoa dropped further off the pace with a bogey on 16. The 23-year-old managed to get one stroke back with a birdie on 17 before a par at the last.
'It's alright to have a so-so round today,' said Ochoa. 'I'm hoping tomorrow is my good day.'
Mi Hyun Kim, a two-time runner-up at this event, shot an even-par 72. She stands alone in seventh place.
Laura Davies, the 2001 champion, notched her third straight round of 1-under 71. She shares eighth place at 3-under-par 213 with Tina Barrett, Candie Kung, Patricia Baxter-Johnson, Dorothy Delasin, Mikaela Parmlid and Jenny Rosales.
Kim Saiki, the defending champion, is well off the pace at 2-over-par 218 after a round of 73.