Ko held off a strong late challenge from LPGA Tour rookie, Jennifer Kupcho, who tied for the runner-up position with Shanshan Feng and third-round leader Hyo Joo Kim in the damp conditions which prevailed on day four of the 4th major of the year for women's golf.
For Ko, it was her third LPGA Tour title of the season and her 5th overall after joining the LPGA Tour in early 2018, one of those victories coming at the Women’s Australian Open in her first start as an LPGA Tour cardholder.
For Kupcho, who prior to turning professional in May won the inaugural Augusta National Women’s Amateur, her runner-up finish secures her LPGA status for 2020.
Hannah Green recovered from a slow start to the week when only just making the cut to finish in a share of 30th with her fellow countrywoman Katherine Kirk.
Su Oh was 44th and Sarah Kemp 65th.
The LPGA Tour now heads to Woburn in Milton Keynes in England for this week’s Women’s British Open, the fifth and final major of the year.
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