Lewis produced a last round of 65 to hole out yet another fast finished in Lydia Ko who shared second position with Cristie Kerr and Angela Stanford.
Lewis recorded a final nine of 31 which included three birdies in her last four holes to catch and pass Ko, Kerr and Stanford for her third win of the season to go also with her four runner-up finishes.
"This place means so much to me," said an emotional Lewis after her round referring to her history in the Rogers area. "I feel like if I go any other place to school then I don't end up where I am. I am fortunate to have gotten around a lot of good people here."
"Today I didn't have my best ball striking day but I found a way to get the ball in the hole those last few holes."
Lydia Ko's runner-up performance was enough to move her past Inbee Park and into second position in the world ranking.
Katherine Kirk (47th) and Julia Boland (57th) were the best of the Australians and only ones to make the cut.
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