Lee, a two time winner on the LPGA Tour, eagled her final hole to join the lead while Martin, a former Women’s British Open winner, stormed home with a final nine 31.
Olson and LPGA rookie Torres have yet to win on the LPGA Tour although Torres, after a slow start to her first season, has begun to display her considerable talent as the season has worn on.
Recent Women’s British Open winner and runner-up at her last start in Portland, Georgia Hall, continues her good form to be just two from the lead and tied with Canada’s Brooke Henderson.
West Australian Minjee Lee improved sharply on her opening 72 with a round of 68 to be tied for 26th at 2 under and six shots from the lead, her only hiccup on day two coming with a bogey at the 10th hole.
Lee's fellow Australian, Katherine Kirk, was unable to repeat her impressive opening day form a round of 73 dropping her back to a share of 30th at 1 under and 1 behind Lee.
Former winner of the event, Lydia Ko, was the only other Australasian to make it to the weekend, the Aucklander recovering from an early double bogey and a threat of a missed cut with a round of 70 to be in a share of 36th place at even par.
Hannah Green, Sarah Jane Smith, Sarah Kemp and Su Oh all missed the cut, Oh forced to withdraw after a horror opening round of 79.
GEORGIA HALL - NO TAKEAWAY PUTTING DRILL
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