Brett Lawrie
This may come as a surprise, but Brett Lawrie has the highest WAR of any Canadian-born player in Blue Jays history (per Stathead). The Langley, BC native played 345 games for the team from 2011 to 2014, mostly at third.
Provided by Stathead.com: View Stathead Tool Used
The majority of his WAR was acquired in the field, where he was one of baseball’s best gloves, ranking 8th in defensive WAR among American Leaguers during his time in Toronto. Lawrie also gets bonus points for being the centrepiece in the package that brought 2015 AL MVP Josh Donaldson to the Jays.