The world golf number one Lydia Ko has improved to a share of 32nd at the latest LPGA tour event in Ontario.
The New Zealander carded an impressive 3rd round 68 that featured a bogie three birdies and an eagle, to take her to 9 under for the tournament.
The leader Suzann Pettersen saved par after a deft bunker shot at the final hole to hold a one-stroke advantage.
She carded a six-under-par 66 on the Whistle Bear course in Cambridge to move to 19 under for the tournament and within sight of a 15th LPGA title and her first since 2013.
But the 34-year-old Norwegian will not be planning her victory speech just yet, with two classy players breathing down her neck on a course that is yielding low scores.
Colombian Mariajo Uribe (67) is just one stroke behind, while veteran American Cristie Kerr (67) trails by two after draining a 20-foot birdie putt from off the putting surface at the final hole.
Ko's closest rival in the rankings, the world number two Park Inbee from Korea, is level with Ko on 9 under.