Americans Paula Creamer and Jane Park remained joint leaders after second-round 71s in the HSBC Women's Champions in Singapore on Friday.
But Brazilian Angela Park, the other player to open the event at Tanah Merah with a five-under-par 67, fell all the way back to 20th spot with a 76.
World number one Lorena Ochoa, winner by a massive 11 shots from the now-retired Annika Sorenstam last year, slipped from sixth to 11th after a 73.
Creamer, bothered by an upset stomach on the first day, again managed to turn in 34, but bogeys at the 11th and 14th lost her the outright lead before she added another birdie on the 16th.
Park matched that, however, to join her on six under and after both fired their approaches to the final hole over the green and close to the water they managed to save their pars to stay one ahead of Australian Katherine Hull and Korean Mi-Hyun Kim.
American Juli Inkster, at 48 trying to become the oldest winner in the history of the LPGA Tour, bogeyed the last two holes to drop from two behind to four back.
Collated second round scores & totals in the LPGA Tour HSBC Women's Champions, Tanah Merah Country Club, Garden Course, Changi, Singapore
(USA unless stated, par 72):
138 Paula Creamer 67 71, Jane Park 67 71
139 Mi-Hyun Kim (Kor) 71 68, Katherine Hull (Aus) 70 69
140 Ai Miyazato (Jpn) 68 72, Sun Young Yoo (Kor) 71 69
141 Lindsey Wright (Aus) 72 69, Se Ri Pak (Kor) 69 72, Angela Stanford 69 72, Shanshan Feng (Chn) 70 71
142 Eun Hee Ji (Kor) 69 73, Meena Lee (Kor) 72 70, Juli Inkster 72 70, Amy Yang 73 69, Lorena Ochoa (Mex) 69 73, Song-Hee Kim (Kor) 72 70, Suzann Pettersen (Nor) 72 70, Michele Redman 70 72, Seon Hwa Lee (Kor) 68 74
143 Anja Monke (Ger) 73 70, Ya-Ni Tseng (Kor) 72 71, Natalie Gulbis 70 73, Karrie Webb (Aus) 74 69, Angela Park (Bra) 67 76, Kristy McPherson 72 71, Gwladys Nocera (Fra) 69 74
144 Russy Gulyanamitta (Tha) 72 72, Momoko Ueda (Jpn) 71 73, Cristie Kerr 73 71, Alena Sharp (Can) 72 72, Hee Young Park (Kor) 72 72
145 Ji-Yai Shin (Kor) 72 73, Jimin Kang (Kor) 72 73, In Kyung Kim (Kor) 71 74, Catriona Matthew (Sco) 72 73, Hee-Won Han (Kor) 73 72, Ji-Hee Lee (Jpn) 73 72, Brittany Lang 71 74
146 Heather Young 70 76, H J Choi (Kor) 72 74, Ji-Young Oh (Kor) 71 75, Na Yeon Choi (Kor) 74 72, Teresa Lu (Tai) 72 74, Christina Kim 73 73
147 Jee Young Lee (Kor) 73 74, Karen Stupples (Eng) 73 74, Il Mi Chung (Kor) 71 76, Louise Friberg (Swe) 71 76, Jin Joo Hong (Kor) 76 71, Wendy Ward 73 74
148 Minea Blomqvist (Fin) 73 75, Giulia Sergas (Ita) 77 71, Pornanong Phatlum (Tha) 75 73, Morgan Pressel 73 75, Carin Koch (Swe) 71 77, Laura Diaz 75 73, Janice Moodie (Sco) 74 74
149 Stacy Prammanasudh 73 76, Shiho Oyama (Jpn) 72 77, Sandra Gal (Ger) 73 76, Katie Futcher 72 77
150 Rachel Hetherington (Aus) 77 73, Young Kim (Kor) 76 74, Helen Alfredsson (Swe) 77 73
151 Ashleigh Simon (Rsa) 80 71, In-Bee Park (Kor) 74 77, Sophie Gustafson (Swe) 72 79, Candie Kung (Tai) 74 77
153 Leta Lindley 73 80
154 Jill McGill 82 72, Becky Morgan (Wal) 79 75
155 Nicole Castrale 77 78, Pat Hurst 76 79
158 Allison Fouch 82 76, Laura Davies (Eng) 81 77, Diana D'Alessio 81 77
161 Poh Joey (Sin) 78 83
163 Vicky Hurst 79 84
HULL LEADS THE WAY
Fired coach Gruden ready for next opportunity
