The 1991 Canadian Grand Prix was a Formula One motor race held at Circuit Gilles Villeneuve on 2 June 1991. It was the fifth race of the 1991 FIA Formula One World Championship. The 69-lap race was won by Nelson Piquet, driving a Benetton-Ford. Piquet took the 23rd and final win of his F1 career after old rival Nigel Mansell, driving a Williams-Renault, suddenly stopped halfway round the last lap while leading by almost a minute. Stefano Modena took second in a Tyrrell-Honda, while Mansell's team-mate Riccardo Patrese was third, having started from pole position. Piquet's win was the first for a car using Pirelli tyres since the 1986 Mexican Grand Prix. This was the last win for a car using Pirelli tyres until the 2011 Australian Grand Prix. Pre-race Between the Monaco and Canadian Grands Prix, Cesare Fiorio had been fired as team manager of Ferrari and had been replaced by Piero Ferrari. Meanwhile, John Barnard had left as Benetton's technical director; he was replaced by Gordon Kimball (father of future IndyCar driver Charlie Kimball). The Circuit Gilles Villeneuve had been modified from the year before: the right-left sequence before the start-finish straight was altered to slow cars down. On the driver front, Julian Bailey's funding ran out and he was replaced at Lotus by Johnny Herbert, who subsequently failed to qualify for the race, while Alex Caffi was out of action for Footwork as a result of injuries sustained in a road accident. His place was taken by Stefan Johansson. Qualifying Pre-qualifying report As at the previous Grand Prix in Monaco, the pre-qualifying session was dominated by the Scuderia Italia Dallara cars, and the Jordans. With Dallara's Emanuele Pirro fastest ahead of his team-mate JJ Lehto, followed by Jordan's Andrea de Cesaris and Bertrand Gachot, there was over a second between the four pre-qualifiers and the rest. Those who failed to progress to the main qualifying sessions included Olivier Grouillard, fifth fastest for Fondmetal, his best result of the season so far. The Modena team was starting to run into financial difficulties, and the performance of their Lambo cars was also slipping, as Nicola Larini and Eric van de Poele ended the session down in sixth and seventh positions. Slowest was Pedro Chaves in the Coloni, despite a new Hart-prepared Cosworth DFR engine. Pre-qualifying classification Qualifying report In practice Riccardo Patrese had a huge accident, walking away unhurt.