Ko has been in consistently good form this season and finished 3rd last week at the LPGA Championship and must therefore be a real chance of making it a three-peat this week.
The London Hunt and Country Club in London in Ontario will stage this week's event with the leading three players in the game, statistically, Stacy Lewis, Inbee Park and Ko likely to vie for favouritism.
Brittany Lincicome, who last week so agonisingly lost a playoff for the Wegman's LPGA Championship, won this event in 2011
Karrie Webb, Katherine Kirk, Lindsey Wright, Sarah Jane Smith, Sarah Kemp, Stacey Keating, Julia Boland and Emma de Groot of Sydney, who qualified on Monday, are the Australians in the field.
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