Justin Wilson will go into Toronto qualifying among the favorites for pole after a superb performance in final practice this morning.
Having been second in both sessions yesterday, the Dreyer & Reinbold Racing driver quickly took the top spot today. He was briefly pushed back to third by Penske's Helio Castroneves and Ryan Briscoe, before responding with a 1m01.1837s lap that put Wilson four tenths clear of the field.
KV Racing's EJ Viso jumped to second near the end, 0.2889 seconds down on Wilson, while Friday afternoon pacesetter Ryan Hunter-Reay was third for Andretti Autosport.
Castroneves and Briscoe ended up fourth and sixth, split by Tony Kanaan in the next of the Andretti entries.
The session was twice halted by full course yellows, first when Raphael Matos crashed his De Ferran Dragon car at Turn 6, then later when Milka Duno (Dale Coyne Racing) had an incident and stalled at the first corner.