Scott Dixon extended his lead at the top of the Verizon IndyCar Series drivers' standings to 62 points after dominating Sunday's race in Toronto as his chief title rivals hit trouble.

Starting second on the grid, Dixon was able to capture the lead when pole-sitter and closest championship rival Josef Newgarden made contact with the wall during a Full Course Yellow following the first round of pit stops, forcing Penske to bring the American into the pits so his car could be checked over.

Dixon retained his advantage through a chaotic race for runners further back as six cars were caught up in an incident at Turn 1 on the race restart following Full Course Yellow, with title contenders Will Power and Alexander Rossi among those affected, the latter's car being thrown into the air briefly in the collision. the longest-serving motorsport website in the world

Despite pressure from Robert Wickens and, after passing for second place at the final round of pit stops, Simon Pagenaud, Dixon held firm to cross the line five seconds clear of the pack and score his fourth victory of the season for Chip Ganassi Racing.

With Newgarden finishing the race down in ninth, Dixon now leads by 62 points with five races remaining, with Rossi a further eight points back in third.

Pagenaud salvaged a decent result for Penske by finishing second ahead of Wickens, who took a podium finish on home soil in third ahead of Schmidt Peterson Motorsports teammate and compatriot James Hinchcliffe in P4.

Charlie Kimball managed to dodge the drama to score Carlin's first top-five finish in IndyCar, taking P5 ahead of Tony Kanaan and Zach Veach. Rossi ended the race eighth ahead of Newgarden, with Marco Andretti completing the top 10 positions.