Stacy Lewis carded a 6-under 66 on Friday to jump into the top spot of the HSBC Women's Champions.
Lewis finished two rounds at the Sentosa Golf Club's Serapong Course at 11- under-par 133, which is two strokes ahead of six players. She is coming off a third-place finish at the Honda LPGA Thailand last week and is seeking her sixth LPGA title
"Any time you come into a new season, there's unknowns of how your game is going to come out," said Lewis. "You just never know how your body is going to react even though you've been there before."
First-round leader Azahara Munoz is among the players in second place following a 2-under 70 on Friday. She is joined by world No. 2 Na Yeon Choi (66), Ariya Jutanugarn (66), Chella Choi (67), Paula Creamer (67) and Sun Young Yoo (68).
Danielle Kang carded a 3-under 69 in her second round to sit alone in eighth place at 7-under 137, while Pornanong Phatlum (71) is a stroke behind in ninth.
Lewis entered the day trailing Munoz by two strokes, but wasted no time in taking the lead as she opened her round with a birdie at the first and later followed with consecutive birdies at the fifth and sixth.
After pouring in five straight pars from there, the world No. 3 and 2012 LPGA Tour Player of the Year closed out her bogey-free round with birdies at the 12th, 14th and 17th to take sole possession of the lead.
Munoz, meanwhile, stumbled to a bogey at the third before quickly getting that stroke back with a birdie at the fourth.
Another birdie at the eighth made her 1-under at the turn, and she then opened her inward nine with a birdie at the 10th.
A birdie at the 13th dropped her to 10-under for the tournament and moved her into a share of first place with Lewis, but a bogey at the par-4 15th coupled with Lewis' final birdie pushed Munoz into the group tied for second.
World No. 1 Yani Tseng recorded a seven on the par-5 fourth and one birdie on Friday en route to a 1-over 73 to fall into a tie for 21st, while 2012 champion Angela Stanford carded her second straight 76 to drop to 8-over for the tournament.
NOTES: Lewis has not finished higher than ninth in her previous three starts at this event ... Munoz is trying for her second career victory ... Jutanugarn's sister, Moriya, is also in the field and is tied for 21st at 3- under 141 following a 68 on Friday ... Moriya was added to the field after Ai Miyazato withdrew prior to the start of her first round due to whiplash suffered during a car accident on Sunday that also included Suzann Pettersen and Creamer.