
Following an incident-packed Mid-Ohio round, in which he was involved in tangles with team-mates Romain Grosjean and Devlin deFrancesco, Rossi stormed to the fastest time on the Toronto street track with a 1m00.609s lap that was 0.090s quicker than Meyer-Shank Racing's Pagenaud.
Rahal Letterman Lanigan Racing's Graham Rahal was also within a tenth of the outright pace in third, with championship leader Marcus Ericsson (Chip Ganassi Racing) and two-time Toronto winner Josef Newgarden (Team Penske) completing the top five.