1991 Canadian Grand Prix
Race 5 of 16 in the 1991 Formula One World Championship
Race details
Date	2 June 1991
Location	Circuit Gilles Villeneuve Montreal, Quebec, Canada
Course	Temporary street circuit
Course length	4.430 km (2.753 miles)
Distance	69 laps, 305.670 km (189.935 miles)
Weather	Mild with temperatures approaching 25 °C (77 °F); Wind speeds up to 12 km/h (7.5 mph)[1]
Pole position
Driver	Riccardo Patrese	Williams-Renault
Time	1:19.837
Fastest lap
Driver	Nigel Mansell	Williams-Renault
Time	1:22.385 on lap 65
Podium
First	Nelson Piquet	Benetton-Ford
Second	Stefano Modena	Tyrrell-Honda
Third	Riccardo Patrese	Williams-Renault
Lap leaders

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.

Between the Monaco and Canadian Grands Prix, Cesare Fiorio had been fired as team manager of Ferrari and had been replaced by Piero Ferrari.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.

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.^[2]

Pos	No	Driver	Constructor	Time	Gap
1	21	Emanuele Pirro	Dallara-Judd	1:23.244	—
2	22	JJ Lehto	Dallara-Judd	1:23.480	+0.236
3	33	Andrea de Cesaris	Jordan-Ford	1:23.672	+0.428
4	32	Bertrand Gachot	Jordan-Ford	1:23.719	+0.475
5	14	Olivier Grouillard	Fondmetal-Ford	1:24.795	+1.551
6	34	Nicola Larini	Lambo-Lamborghini	1:25.736	+2.492
7	35	Eric van de Poele	Lambo-Lamborghini	1:26.900	+3.656
8	31	Pedro Chaves	Coloni-Ford	1:34.475	+11.231

In practice Riccardo Patrese had a huge accident, walking away unhurt. In the qualifying sessions, Patrese took pole position from team-mate Mansell, out-qualifying him for the fifth straight race. Senna was third followed by Prost, Moreno, Berger, Alesi, Piquet, Modena, and Pirro.

Pos	No	Driver	Constructor	Q1	Q2	Gap
1	6	Riccardo Patrese	Williams-Renault	1:37.593	1:19.837	—
2	5	Nigel Mansell	Williams-Renault	1:35.065	1:20.225	+0.388
3	1	Ayrton Senna	McLaren-Honda	1:35.843	1:20.318	+0.481
4	27	Alain Prost	Ferrari	1:36.003	1:20.656	+0.819
5	19	Roberto Moreno	Benetton-Ford	1:35.897	1:20.686	+0.849
6	2	Gerhard Berger	McLaren-Honda	1:38.223	1:20.916	+1.079
7	28	Jean Alesi	Ferrari	1:35.257	1:21.227	+1.390
8	20	Nelson Piquet	Benetton-Ford	1:37.354	1:21.241	+1.404
9	4	Stefano Modena	Tyrrell-Honda	1:38.218	1:21.298	+1.461
10	21	Emanuele Pirro	Dallara-Judd	1:39.017	1:21.864	+2.027
11	33	Andrea de Cesaris	Jordan-Ford	1:37.097	1:22.154	+2.317
12	3	Satoru Nakajima	Tyrrell-Honda	1:41.100	1:22.262	+2.425
13	16	Ivan Capelli	Leyton House-Ilmor	1:40.906	1:22.443	+2.606
14	32	Bertrand Gachot	Jordan-Ford	1:38.383	1:22.596	+2.759
15	24	Gianni Morbidelli	Minardi-Ferrari	1:39.780	1:22.993	+3.156
16	25	Thierry Boutsen	Ligier-Lamborghini	1:38.517	1:23.040	+3.203
17	22	JJ Lehto	Dallara-Judd	1:38.435	1:23.040	+3.203
18	23	Pierluigi Martini	Minardi-Ferrari	1:37.864	1:23.125	+3.288
19	29	Éric Bernard	Lola-Ford	1:38.013	1:23.260	+3.423
20	7	Martin Brundle	Brabham-Yamaha	1:38.405	1:23.516	+3.679
21	9	Michele Alboreto	Footwork-Porsche	1:41.196	1:23.529	+3.692
22	30	Aguri Suzuki	Lola-Ford	1:39.696	1:23.585	+3.748
23	15	Maurício Gugelmin	Leyton House-Ilmor	1:38.689	1:23.650	+3.813
24	11	Mika Häkkinen	Lotus-Judd	1:42.900	1:23.923	+4.086
25	10	Stefan Johansson	Footwork-Porsche	1:49.019	1:24.433	+4.596
26	26	Érik Comas	Ligier-Lamborghini	1:39.670	1:24.460	+4.623
27	18	Fabrizio Barbazza	AGS-Ford	1:40.555	1:24.491	+4.654
28	17	Gabriele Tarquini	AGS-Ford	1:41.946	1:24.653	+4.816
29	8	Mark Blundell	Brabham-Yamaha	1:39.897	1:24.661	+4.824
30	12	Johnny Herbert	Lotus-Judd	1:39.113	1:24.732	+4.895

At the start, Mansell got away well and led Patrese, Senna, Prost, Berger, and Moreno. Berger went out on lap 4 with electronics problems, while Aguri Suzuki retired when his Lola caught fire. Moreno was out on lap 10 when he spun off, while Prost was suffering from gearbox problems. The Frenchman had managed to hold on while he engaged in a battle with teammate Alesi and Piquet's Benetton.

Mansell led Patrese and Senna on lap 25 when Senna retired, leaving Mansell and Patrese a long way ahead of the Alesi–Prost–Piquet battle. This ended Senna's thus far perfect season, capping his winning streak at 4. Prost retired shortly after with a gearbox failure on lap 27 and Ferrari's misery was compounded on lap 34 when Alesi's engine blew up.

The Williams drivers were now well ahead of the pack, but Piquet closed on Patrese, the Italian suffering from gearbox troubles of his own. In the late stages Patrese was passed by Stefano Modena in the Tyrrell. On the last lap, Mansell led from Piquet, Modena, Patrese, de Cesaris, and Gachot when he suddenly slowed to a halt at the hairpin. There were rumours that Mansell had failed to change gear for the hairpin and stalled the car, or that he had turned off the engine accidentally while waving to the crowd during the final lap. Mansell denied this, saying that the gearbox had gone into neutral as he shifted down, and Williams said that the car had suffered an electrical failure. This is technically true, but was induced by Mansell failing to keep the revs sufficiently high on the engine to drive the electrical and hydraulic systems, thus causing the gearbox barrel to get stuck. When the car was returned to the pits, the engine was re-fired and the gearbox worked perfectly.^[3][4] Piquet thus took an unexpected victory for Benetton at the expense of his old rival Mansell, who was classified sixth. Jordan's five points, their first in Formula One, meant that they would no longer have to pre-qualify when the draw was reshuffled at the halfway point of the season.

The race was Nelson Piquet's 23rd and last win in Formula One, and Stefano Modena's second and last podium finish.^[5]

Pos	No	Driver	Constructor	Tyre	Laps	Time/Retired	Grid	Points
1	20	Nelson Piquet	Benetton-Ford	P	69	1:38:51.490	8	10
2	4	Stefano Modena	Tyrrell-Honda	P	69	+ 31.832	9	6
3	6	Riccardo Patrese	Williams-Renault	G	69	+ 42.217	1	4
4	33	Andrea de Cesaris	Jordan-Ford	G	69	+ 1:20.210	11	3
5	32	Bertrand Gachot	Jordan-Ford	G	69	+ 1:22.351	14	2
6	5	Nigel Mansell	Williams-Renault	G	68	Electrics	2	1
7	23	Pierluigi Martini	Minardi-Ferrari	G	68	+ 1 lap	18
8	26	Érik Comas	Ligier-Lamborghini	G	68	+ 1 lap	26
9	21	Emanuele Pirro	Dallara-Judd	P	68	+ 1 lap	10
10	3	Satoru Nakajima	Tyrrell-Honda	P	67	+ 2 laps	12
Ret	15	Maurício Gugelmin	Leyton House-Ilmor	G	61	Engine	23
Ret	22	JJ Lehto	Dallara-Judd	P	50	Engine	17
Ret	10	Stefan Johansson	Footwork-Porsche	G	48	Throttle	25
Ret	16	Ivan Capelli	Leyton House-Ilmor	G	42	Engine	13
Ret	28	Jean Alesi	Ferrari	G	34	Engine	7
Ret	29	Éric Bernard	Lola-Ford	G	29	Gearbox	19
Ret	27	Alain Prost	Ferrari	G	27	Gearbox	4
Ret	25	Thierry Boutsen	Ligier-Lamborghini	G	27	Engine	16
Ret	1	Ayrton Senna	McLaren-Honda	G	25	Alternator	3
Ret	11	Mika Häkkinen	Lotus-Judd	G	21	Spun off	24
Ret	7	Martin Brundle	Brabham-Yamaha	P	21	Engine	20
Ret	24	Gianni Morbidelli	Minardi-Ferrari	G	20	Spun off	15
Ret	19	Roberto Moreno	Benetton-Ford	P	10	Suspension	5
Ret	2	Gerhard Berger	McLaren-Honda	G	4	Injection	6
Ret	30	Aguri Suzuki	Lola-Ford	G	3	Fuel leak	22
Ret	9	Michele Alboreto	Footwork-Porsche	G	2	Throttle	21
DNQ	18	Fabrizio Barbazza	AGS-Ford	G
DNQ	17	Gabriele Tarquini	AGS-Ford	G
DNQ	8	Mark Blundell	Brabham-Yamaha	P
DNQ	12	Johnny Herbert	Lotus-Judd	G
DNPQ	14	Olivier Grouillard	Fondmetal-Ford	G
DNPQ	34	Nicola Larini	Lambo-Lamborghini	G
DNPQ	35	Eric van de Poele	Lambo-Lamborghini	G
DNPQ	31	Pedro Chaves	Coloni-Ford	G
Source:[6][7]

Drivers' Championship standings Pos Driver Points 1 Ayrton Senna 40 2 Nelson Piquet 16 3 Alain Prost 11 4 Riccardo Patrese 10 5 Gerhard Berger 10 Source: [8]

Constructors' Championship standings Pos Constructor Points 1 McLaren-Honda 50 2 Benetton-Ford 19 3 Williams-Renault 17 4 Ferrari 16 5 Tyrrell-Honda 11 Source: [8]

• Note: Only the top five positions are included for both sets of standings.