With Jackie Stewart having won the Drivers' World Championship in Italy two weeks earlier, the major interest was over the Constructors' title which was finely balanced between Tyrrell and Lotus. Tyrrell decided to enter three cars for the Canadian race and as Patrick Depailler was out of action after a motorcycle accident Tyrrell decided to run Chris Amon, who had fallen out with Tecno. BRM had hired Peter Gethin to replace Clay Regazzoni, while Ferrari had only one car again as Jacky Ickx had left the team. Tim Schenken made his comeback as Howden Ganley's partner at Williams and Jody Scheckter reappeared in a third McLaren for the first time since he had triggered the big accident at Silverstone.

Qualifying resulted in pole position going to Ronnie Peterson (Lotus) with Peter Revson alongside him on the front row of the grid. Scheckter shared the second row with Carlos Reutemann (Brabham) while Emerson Fittipaldi (Lotus) and François Cévert - the pair still fighting over second place in the title - were on the third row. The top 10 was completed by Denny Hulme (McLaren), Niki Lauda (BRM), Stewart and Wilson Fittipaldi (Brabham).

It was raining on race day and at the start Peterson took the lead with Scheckter chasing and then a fast-startring Lauda. Emerson Fittipaldi was fourth ahead of Stewart, Reutemann, Revson and the rest. In the early laps Lauda was the man on the move and he moved into the lead on lap three, leaving Peterson and Scheckter to fight over second, which they did until Peterson crashed on lap 17. By then Scheckter had dropped back behind Fittipaldi and Carlos Pace (Surtees). On lap 20 Lauda pitted for a change of tires and that left Fittipaldi in the lead with Jackie Oliver (Shadow) second and Cévert third. There was considerable confusion after Cévert and Scheckter collided on lap 33 after which there was bungled pace car interlude after which things became very confused as this failed to pick up the leader and allowed those ahead to gain almost a lap. All this meant that Oliver ended up in the lead with Revson second and Beltoise third. Of these three Revson had the most competitive car and so eventually moved into the lead and led all the way to the flag while Fittipaldi charged to try to make up for lost ground and overtook Oliver and Beltoise in the closing laps to grab second. For hours after the race confusion reigned but eventually it was confirmed that Revson was the winner - thanks to a lucky break when the pace car came out.