Choi: two-shot lead
140 Na Yeon Choi (Kor) 69 71
142 Paula Creamer 68 74, Angela Stanford 69 73, Lorena Ochoa (Mex) 69 73, Song-Hee Kim (Kor) 69 73
143 Ji-Yai Shin 67 76 (Kor), Ya-Ni Tseng (Tai) 69 74, Katherine Hull (Aus) 70 73
144 Seon Hwa Lee 75 69 (Kor), Suzann Pettersen (Nor) 74 70
145 Juli Inkster 73 72
146 Annika Sorenstam (Swe) 69 77, Eun Hee Ji (Kor) 73 73, Cristie Kerr 73 73, Hee-Won Han (Kor) 75 71
148 In-Bee Park (Kor) 77 71, Jeong Jang (Kor) 72 76, Helen Alfredsson (Swe) 75 73
150 Karrie Webb (Aus) 74 76
152 Angela Park (Bra) 76 76
Na Yeon Choi claimed the half-way lead at the LPGA Samsung World Championship with a one-under-par second round of 71.
The South Korean is four-under for the tournament, two clear of a goup of four players that includes world number one Lorena Ochoa.
On a day when difficult, windy weather pushed scores up at Half Moon Bay in California, Choi took advantage of more favourable early conditions with two birdies during a front-nine of 33.
Her progress was, however, stalled by consecutive bogeys at the 12th and 13th, although she pulled things round to finish with a birdie at the par-five 18th.
Ochoa, the two-time defending champion, had briefly taken control with five straight birdies from the fourth.
But as the wind kicked up, her birdie blitz ended with a double-bogey at the par-three ninth, soon followed by another at the par-four 13th.
And the Mexican dropped further shots at 16th and 18th to eventually sign for a 73 and a share of second place.
Ochoa was joined at two-under by South Korea's Song-Hee Kim (73) and Americans Angela Stanford (73) and Paula Creamer (74).

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