The 1984 Detroit Grand Prix was a Formula One motor race held on June 24, 1984 in Detroit, Michigan. It was the eighth race of the 1984 Formula One World Championship. The 63-lap race was won from pole position by Brazilian driver Nelson Piquet, driving a Brabham-BMW. Englishman Martin Brundle finished second in a Tyrrell-Ford, less than a second behind Piquet, before the Tyrrell team were disqualified from the championship for various alleged rule infringements. Italian Elio de Angelis was thus promoted to second in his Lotus-Renault with another Italian, Teo Fabi, third in the other Brabham-BMW. Pre-race After breaking his leg at the Monaco Grand Prix three weeks before, and subsequently withdrawing from the next race in Canada, Patrick Tambay was back driving for the works Renault team. Mario Andretti, who had been called in as a possible replacement for Tambay in the race, was satisfied to spend the weekend as a spectator, watching his two sons run in the support races. Elsewhere, a lack of Hart turbo engines meant that the Spirit team were forced to modify their car to accommodate a naturally-aspirated Ford Cosworth DFV for this race. Qualifying report Qualifying saw Nelson Piquet take pole position in his Brabham-BMW, his second in succession and fourth of the season, by over 0.6 seconds from Alain Prost in the McLaren-TAG. Nigel Mansell, having set the fastest time in the Friday session in his Lotus-Renault, was third, a further 0.5 seconds behind, with Michele Alboreto fourth in the Ferrari. On the third row of the grid were Mansell's teammate Elio de Angelis and Derek Warwick in the factory Renault, and on the fourth row were Ayrton Senna in the Toleman and Eddie Cheever in the Alfa Romeo. Patrick Tambay in the second Renault and Niki Lauda in the second McLaren completed the top ten. Piquet's teammate Teo Fabi could only manage 23rd, while Huub Rothengatter came 27th and last in the Spirit-Ford and thus failed to qualify. Qualifying classification Race report Warm and sunny weather returned on Sunday after an overnight storm had washed the track clean, but at the green light, there was immediate chaos. Nigel Mansell had decided that he could get by Nelson Piquet off the grid and aimed his Lotus for the space between Piquet's Brabham and Alain Prost's McLaren. He struck the back of Prost and bounced into the side of Piquet, sending the