The race which was contested over 80 laps, was won by Peter Revson after starting from second on the grid, driving a McLaren M23. This turned out to be Revson's last victory and podium finish in Formula One. As of 2015, this is the last Grand Prix to be won by an American born driver. Emerson Fittipaldi took second position for Team Lotus, while Jackie Oliver took his first podium in five years, and would turn out to be his last.
The race began in very wet conditions, which caused a number of incidents later in the race. François Cevert and Jody Scheckter collided on the 32nd lap, resulting in the deployment of a safety car for the first time in Formula One history (although the sport would wait until 1993 before giving an official role to these cars). The car in question was a yellow Porsche 914 driven by former F1 privateer Eppie Wietzes. Wietzes stayed in front of Howden Ganley's Iso-Marlboro car by mistake, which allowed several drivers including eventual winner Revson, to gain a lap on the field. Confusion immediately set in, with some believing the leader to be Ganley and others, including Team Lotus manager Colin Chapman, believing it to be Fittipaldi. Pit stops at the time were unusual. Formula One had only recently switched to slick tyres but the drying conditions necessitated stops mid-race. The small pit lane at Mosport became busy, with a number of drivers heading into the pit lane only to have to drive through as there was no room for them to be serviced. Ganley realised the problem and waited until teammate Tim Schenken had made his stop, making him one of the last to stop. The pit stops caused significant confusion, Chapman even went as far as to perform his traditional victory celebration of tossing his cap in the air at the end of what he believed to be the 80th lap, even though Fittipaldi was not shown the checkered flag. After a long pause, the starter waved the flag over a group of cars consisting of Ganley, Hailwood, Revson and Hunt. Despite seeing the flag first, Ganley did not believe he had won the grand prix despite lap charts kept by the team showing him leading. The officials then announced Revson as the winner after a long confusion which included protests from Ganley's then girlfriend (later wife) who had been keeping the teams lap chart. Ganley maintains he feels he won the race, citing the fact official lap charts have him pitting when he didn't.
Chris Amon was brought into the Tyrrell team in order to try and help with constructors points. He finished way out of the points, three laps down. Team Lotus was able to take the lead from Tyrrell in the constructors championship in the final results.
Note: Only the top five positions are included for both sets of standings. Only the best 7 results from the first 8 races and the best 6 results from the last 7 races counted towards the Championship. Numbers without parentheses are Championship points; numbers in parentheses are total points scored.