Lee disappointingly bogeyed her final two holes for her round of 71 while Monday qualifier for the event, Hillier, dropped her only shot of the day at the 16th hole in an otherwise solid start to an event in which she has missed the cut in her only two starts to date.
Fellow Australians, Su Oh and Sarah Kemp, finished on even par 72, Hannah Green 73, Karrie Webb 75 and Katherine Kirk 76.
Recent KPMG PGA Champion, Green, recorded five birdies in her round but double bogeys at the 4th and 12th holes and two late bogeys saw her finish in a share of 62nd place.
The leader, Buhai, has yet to win on the LPGA Tour but won the Ladies South African Open at the age of 14 and again at 17 and in 2007 was the then youngest player (at 17) to win on the Ladies European Tour when successful at the Catalonia Masters.
She was considered a teenage prodigy at that time although, to date, her LPGA Tour career has not lived up to that expectation.
It has been more than a year since Buhai recorded a top ten on the LPGA Tour so this is quite a form reversal for the now 30-year-old.
Buhai leads by one over American, Danielle Kang, and Japan’s, Hinako Shibuno, but not too far from the lead are world number two, Shun Hyun Park (67), and world number one, Jin Young Ko (68).
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