French teenager Alex Baron clinched his maiden Indy Lights win at Toronto.
Dominating the race from the outset, Baron led home his Belardi Auto Racing team-mate and series leader Gabby Chaves.
Jack Harvey (SPM with Curb-Agajanian) held Andretti Autosport driver Matthew Brabham out of third.
Baron was never headed from his pole position in the 36-lap (40-minute) race to win by 1.2s.
Brabham, who slipped one place from his starting berth early in the race, had a lonely run with his team-mate Zach Veach claiming fifth, 10.5s behind the 20-year-old Indianapolis-based third generation racer.
Chaves almost doubled his lead over Veach by now moving to a 21-point advantage.