The 21-year-old Lee has struggled throughout the year due to
shoulder problems, missing five cuts in a row at one point, but
said she was finally playing to her potential after opening a
three-shot lead at the $2 million LPGA Tour event.
"I injured my shoulder back in February and I didn't know what
was wrong," she told a news conference at the SKY 72 Golf Club.
"I was scared to hit ball, because I didn't know where it was
going to go.
"So it was tough mentally going through that, missing all those
cuts. But I'm very happy with where my game is now."
New Zealander Ko, who has not won on the LPGA Tour since July,
is being pushed hard for the circuit's points title by Thai
Ariya Jutanugarn, who finished one over par on Thursday.
Swede Anna Nordqvist, France's Karine Icher, American Lizette
Salas and Koreans Cho Jeong-min and Kim In-kyung are tied for
second after carding matching 68s.
Defending champion Lexi Thompson is a further two shots adrift.
(Editing by John O'Brien)
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