Oh opened with a round of 67 on Friday and appeared to be struggling early in her second round but with birdies at her 8th, 9th and 13th, holes and an eagle at the 12th she raced into contention and sits behind only Frenchwoman Celine Herbin and Korean Sei Young Kim.
Oh has the par 4th 8th (her 17th hole) and the par 5 9th to finish off her second round in the 54 hole event so the opportunity exists for her to move closer to the lead when she returns early on Sunday morning to finish her opening 36 holes.
Like Oh, Herbin has yet to win on the LPGA Tour and has a best of 28th in 11 starts this season so faces a big task tomorrow while Kim has won six times and was Rookie of the Year in 2015.
Oh, though, has been building form in recent weeks and this could well present a great opportunity for a breakthrough victory.
Of the other Australians Karrie Webb and Rebecca Artis have both comfortably made the cut while Sarah Jane Smith also appears likely to make the final round after a second round of 65 was a bounce-back from her opening 76.
Smith, who birdied her final three holes today, sits on the current cut-line of 1 under but some 36 players have still to finish their second rounds.
SWING LIKE LYDIA KO
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