Choi takes lead at Torrey Pines

South Korea's domination of the Samsung World Championship continued after the third round at Torrey Pines - but it was Na Yeon Choi who raced past her compatriot Jiyai Shin.

The latter led after 18 and 36 holes but was two strokes behind after 54, thanks to a nine-under round of 63 Choi.