On Friday, 6 July 1990 the Paul Ricard Circuit in Le Castellet celebrated its 20th birthday by hosting the French Formula 1 GP for the final time. It was the seventh race of a season that was panning out as expected, with another great duel between Ayrton Senna for McLaren and the world champion Alain Prost, who over the winter had moved to Ferrari and was fresh from victory in Mexico. The Frenchman had already won in Brazil, home of his rival, while Senna had triumphed in Phoenix (in the USA), Monaco and Canada. Riccardo Patrese won the day with the Williams at San Marino.
At the Paul Ricard Ferrari looked like it had when it dominated in Mexico City. Nigel Mansell took pole position and Prost - forced to use a race-tuned engine after his more powerful one had gone up in smoke in the free practices - managed to achieve a place on the grid, too. The Frenchman was fourth, behind the two McLarens of former Ferrari driver Gerhard Berger and Senna.
The tyres were the main worry ahead of the French Grand Prix, the main concern being that two pit stops would be needed to complete the race. But one previously little-considerd team had an ace up its sleeve. Leyton House, formerly March, had a car that adhered so tightly to the regulations that drivers Ivan Capelli and Mauricio Gugelmin failed even to qualify in Mexico. The designer, 27 year old Adrian Newey, had just left the team, but before he went he introduced the CG901 an aerodynamic update that was best suited to the Le Castellet track.
While all the teams were seeking to finish with only one pit stop, Leyton House was preparing a coup: to finish the race without taking any pit stops at all. At the start Berger overtook Mansell while Senna was third ahead of Prost. The early part of the race was slow and it was the pit stops to change tyres that made the difference. Ferrari number one entered the pits on Lap 26 and set off again seven seconds later. Shortly after, Mansell also stopped while the McLarens remained on track beyond Lap 30. Senna overtook Berger who lost 12 seconds in the pits. But Senna himself lost 16 seconds during his own pit stop, creating an opportunity for the Scuderia. Things would have been looking good for Ferrari were it not now clear that the two Leyton House cars would try to go the whole way without stopping.
Mansell was forced to retire while Prost caught up with Gugelmin although overtaking was rather tricky. Leyton House's new aero package allowed the British car to exit the bends better than the Ferrari, which then, on the straight, failed to take advantage of the superior power of its V12 to drive home an attack. Gugelmin held out for a long time but eventually gave way to Prost who slowly also closed in on Capelli. It was the 60th of 80 laps and, again, it was a mistake to think that it would be easy for the Frenchman to overtake the Italian. Capelli was having the best race of his career, one which in fact earned him a salary at Ferrari in 1992. He fought tooth and nail, only succumbing to the Ferrari with three laps to go.
Prost crossed the line first in front of Capelli and Senna. This was Ferrari's 100th win, and Alain, with his second consecutive victory, threw the world championship race open again, now just three points behind the Brazilian. Ferrari led the constructors' rankings, followed by McLaren on 83 points, Lotus 79, and Williams 43. A few hours later, at the Olympic Stadium in Rome, Germany and Argentina kicked off for the World Cup final, but for Italian fans the day's most important match was already won.