The 1991 Monaco Grand Prix was a Formula One motor race held at Monaco on 12 May 1991. It was the fourth race of the 1991 Formula One World Championship. The 78-lap race was won from pole position by Brazilian driver Ayrton Senna, driving a McLaren-Honda. It was Senna's fourth victory from the first four races of the season, and his fourth Monaco win. Englishman Nigel Mansell finished second in a Williams-Renault, with Frenchman Jean Alesi third in a Ferrari. Qualifying Pre-qualifying report The pre-qualifying session on Thursday morning ended up being somewhat straightforward for Dallara and Jordan. JJ Lehto was fastest for Dallara, with Emanuele Pirro in third, with Jordan's Andrea de Cesaris and Bertrand Gachot second and fourth. Gachot was over a second faster than the fifth-placed car, the Modena Lambo of Nicola Larini. The other Lambo of Eric van de Poele was sixth, with Pedro Chaves seventh in the Coloni on his first experience of the Monaco circuit. Olivier Grouillard propped up the time sheets for Fondmetal as he continued to gain experience in the new Fomet car. Pre-qualifying classification Qualifying report Ayrton Senna shocked no-one by taking pole position, but second place was a surprise with Stefano Modena taking full advantage of the superior Pirelli qualifying tyres to be second, followed by Patrese, Piquet, a disappointed Mansell, Berger, Prost, Moreno, Alesi, and de Cesaris. Alex Caffi had a huge accident in the swimming pool section on Saturday, after missing Thursday qualifying with a gearbox problem, and did not participate in the race. Elsewhere Martin Brundle was excluded for missing a weight check in Thursday practice. Qualifying classification Race Race report At the start, Senna got away well followed by Modena, Patrese, Mansell, and Prost. In the usual first corner mayhem Berger ran into the back of Piquet, dropping the Austrian to the back of the pack and breaking Piquet's suspension, Berger would later crash out. Senna quickly built up a huge lead over Modena and Patrese. Meanwhile, Andrea de Cesaris in the Jordan was eventually catching up to Jean Alesi and just outside the points in 7th place before retiring shortly after battling with the second Ferrari with a sticking throttle. Meanwhile, Aguri Suzuki in the Lola hit the wall at St. Devote on lap 25 with braking problems, as Modena's teammate Satoru Nakajima had spun and retired at the Nouvelle Chicane after making contact with