Spain's Carlota Ciganda recovered from a bogey on her opening hole to fire a six-under 66 on Friday and move into a share of the lead with South Korean Park In Bee at the halfway stage of the HSBC Women's Champions.
Both women are on nine-under 135 and lead Azahara Munoz by two shots at the US$1.4 million (S$1.9 million) tournament at the Sentosa Golf Club.
Overnight joint-leader Tseng Ya-ni, the Taiwanese former world No. 1, failed to make a birdie at the Serapong Course and signed for a 75. She drops back to tied-17th on 141.
Ciganda, 24, was thrilled by her response after a mistake on the first hole and picked up eight birdies to put herself in prime position for her first LPGA Tour victory.
She said: "I played really well out there today. It gives me a chance for a win. I just have to stay patient."
It will be a packed leaderboard heading into the weekend, with 13 players within four shots of the summit. World No. 1 Lydia Ko had a 70 and is tied for fourth on 138, alongside 2013 winner Stacy Lewis.
Said Park, who is the only golfer in the 63-woman field yet to drop a shot after 36 rounds: "Overall, everything from tee to green was perfect today.
"It could have been a better day but I'm really satisfied with way I finished and especially with no bogeys after two days, which is a great result."
Other notables include American Michelle Wie (70 and joint-23rd), defending champion Paula Creamer (71 and t-36th) while Singapore's representative Koh Sock Hwee signed for a 77 and is last on 156.