China’s Feng, who is looking to become the first player to defend an LPGA title in 2017, birdied seven holes and eagled on the par-5 12th hole.
Japan’s Ai Suzuki followed Feng with a 65, with five stellar birdies and an eagle.
“What was working well was my putting today,” said Feng, a Rio Olympic bronze medalist.
Feng birdied five of her first seven holes Saturday to jump ahead — leading by four shots at one point — before Suzuki fired a 6-under-par 30 on the back nine to a hair’s-breadth of two shots.
“It’s not my first time leading a tournament, but of course it’s my first time (when) maybe I’m not too far away from a title defence,” said Feng.
“Of course, before I came I was like, ‘if I can do it, it would be great,’ but the most important thing I think is to enjoy the whole process and then playing with Ai tomorrow will be fun,” she said.
England’s Charley Hull and South Korea’s Min-Young Lee tied for the third place, sitting at 10-under par.
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