Carlota Ciganda shot a 6-under 66 on Friday to move into a tie for the lead with Inbee Park after the second round of the HSBC Women's Champions.
Ciganda offset a pair of bogeys with eight birdies at Sentosa Golf Club to finish even with Park (69) at 9-under 135.
Azahara Munoz was in third place, two strokes back, after a 67 that featured six birdies against a lone bogey.
Top-ranked Lydia Ko birdied three of the last four holes en route to a 70 that put the 17-year-old in a tie for fourth with Stacy Lewis, Jenny Shin and Karrie Webb at 6-under.
Defending champion Paula Creamer was tied for 36th after a 71. Michelle Wie fired a 70 that included three bogeys, three birdies and an eagle.