Ko, whose love affair with the Lake Merced layout continues having won here on two previous occasions, produced the equal best round of the day to move ahead after a nip and tuck battle with Korda over the closing nine holes.
Ko began day three behind Korda but by her 6th hole she had drawn level after Korda bogeyed her 2nd and 4th holes before a holed bunker shot at the 11th and further birdies at the 15th and 16th holes saw the 21-year old Ko edge clear.
After stunning success earlier in her career Ko has not won in just under two years but this could be the week for her to reverse recent trends and head back towards the top of the world ranking she last held in June of 2017.
“I love San Francisco, I’m a member here so sometimes I get some friendly member bounces, but it brings back a lot of great memories and I knew no matter how well I played I was going to have a fun time,” said Ko after her round.
Lee was the US Junior Girls Champion on this golf course six years ago and today she reeled off a back nine of 32 (including one bogey) to open up the door for her 4th LPGA Tour title.
Former US Amateur Champion Mariajo Uribe of Colombia is tied for 4th at 6 under and five shots from Ko, a position she shares with American Ryan O’Toole, England’s Charley Hull and Thailand’s Moriya Jutanugarn.
Su Oh was one of two other Australians to make the cut but after a fast start to the week she is now in 25th position while Lee's fellow West Australian Hannah Green was the other but is well back in 52nd place.
RULES: UNATTENDED FLAGSTICK
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