Ryu’s round of 64 saw her move one shot clear of Stacy Lewis, Amy Yang and first round leader Mika Miyazato.
Ryu has not won on the LPGA Tour since 2014 but changes to her swing in recent times in work with coach Cameron McCormick, the coqch also of Jordan Spieth, seem now to be kicking in.
She did finish runner-up in this event in 2015 behind Minjee Lee and has two other top tens in three starts at Kingsmill.
Yeah, this one is definitely my favourite golf course what we play,” said Ryu. “I consistently play really well here, so I feel really comfortable to stay here. I think I just really like the atmosphere, so I really enjoy it, so enjoying it makes me play better.
“Actually these days what I'm really focused is got back to confidence. The thing is, I think since Hawaii I played really well. I always feel I'm ready to play well, I'm ready to win a tournament, but I couldn't get enough like confidence. So I think that was the reason why I couldn't really finish well.”
Defending champion, Australia’s Minjee Lee, is just two shots from the lead in a share of 5th position with Su Oh in 14th, Karrie Webb 23rd and Sarah-Jane Smith 52nd.
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