The Charley Hull of england Transferred at Florida Having a third-round 66.
Hull who won the LPGA Tours season finale in 2016 birdies with a bogey in Tiburon Golf Club to reach 11 under and over five shots of pioneer Sei Young Kim.
The Korean retained her edge and posted a bogey-free 68 to venture into the final round a shot clear of the Nelly Korda of America four strokes back.
Kim temporarily maintained a five-shot guide after three birdies on the first seven holes, before finishing a run of pars by holing a 25-footer at the 15th on her way into some bogey-free round.
Korda achieved the turn in 35 but jumped along with five birdies on her back nine, such as a bunker shot in the 11th, while Masson remained in touch with a third-round 70.
Englands Bronte Law took a 68 and is tied for 68 two shots behind Hull, while Georgia Hall is a further two shots back after a 71.
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