OTTAWA — Defending champion Lorena Ochoa shot a bogey-free 6-under-par 66 to take a one-stroke lead over Annika Sorenstam in the Canadian Women's Open, leaving Michelle Wie nine strokes back in her final LPGA Tour event of the year.

Wie, using the last of her six 2008 sponsor exemptions, bogeyed three of her last six holes for a 75. The Punahou School alum and current Stanford freshman needs to win or finish second to avoid a trip to Q-school — if she decides to try qualifying.

Wie birdied Nos. 1 and 3 to get to 2 under, but gave the strokes back with double bogey on the par-5 sixth hole.

Ochoa, the winner last year at Royal Mayfair in Edmonton, Alberta, hit all 18 greens in regulation and was in the rough only once at Ottawa Hunt and Golf Club course.

Se Ri Pak, Nicole Castrale, Meena Lee and Hee-Won Han opened with 68s.