Kim Sei-young took a second-round five to hold a two-shot lead at the halfway point of the LPGAs season-ending Tour Championship.
The South Korean carded six birdies and a bogey to move to 12 under and remain in contention for a 10th LPGA win.
The Caroline Masson of germany is next after shooting at on a 66 to climb the leaderboard.
Englands Georgia Hall, that had made a powerful beginning in Florida, fell down the order.
The 2018 Womens British Open winner carded a five-under 67 in the first round to sit down within two shots of the guide but is currently tied for ninth, six shots off Kim.
There were fortunes for the compatriot Jodi Ewart Shadoff of Hall, that shot a 65 to move to a share of ninth alongside Hall and one ahead of Bronte Law and fellow Englishwomen Charley Hull.
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