Kim let good winning chances slip at the Michelob Ultra Open and in Phoenix earlier in the season but she powered home over the closing nine holes to hold out Pak who was looking for her 25th LPGA Tour victory.
Hee Won Han and Jee Young Lee made it a great day for Korean golf by sharing third with Angela Stanford, in fact seven of the top twelve golfers this week were Koreans.
It was Kim's second LPGA Tour victory following her victory last year in the Longs Drugs Challenge. The 2005 US Junior Champion is establishing herself as one of the best players on the LPGA Tour.
Anna Rawson was the best of the Australians finishing 12th which was a huge turnaround in a season where she has made only one cut in seven starts.
Katherine Hull was 40th and Sarah Jane Smith 60th.
The LPGA Tour now moves to Havre de Grace in Maryland for this week's McDonald's LPGA Championship.
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