Race report
As the grid was in the process of forming up before the start, the McLaren team transferred the settings from Senna's car to Prost's in the hope of curing its handling problem (Prost had actually been more than 2 seconds slower in the race morning warm up than Senna). Prost would later say that while handling and grip were significantly improved, the down on power engine remained and despite the same wing settings he still could not match his teammate for straight line speed. [5]
Senna led from the start and built up a small lead over Berger, while Mansell (whose 'development' V12 engine was not revving right) and especially Prost struggled to stay in touch. Indeed, in the early stages of the race Prost, who was getting used to his cars new set up, was having a hard time holding off the V10 Williams-Renault of Thierry Boutsen, though the BBC's James Hunt explained that Prost was using a harder set of "B" compound tyres in the hope of not having to pit during the race.
Emanuele Pirro was the races first retirement, the transmission in his Benetton-Ford not lasting a single lap. Only just longer was the Lola-Lamborghini of Philippe Alliot. The V12 powered Lolas of Alliot and Michele Alboreto had easily been the fastest in pre-qualifying, and Alliot went on to qualify a fine 7th (ahead of the Benetton's) before spinning into the sand trap at Ascari on just his second lap.
Alessandro Nannini's Benetton lost its brakes on lap 33 putting him into retirement, while Nigel Mansell suffered gearbox failure on lap 41. Through all of this, Senna was still comfortably in the lead with Prost having fought his way past Berger into second following Mansell's retirement. Prost passed Berger in front of the pits and the main grandstand and this saw the unusual sight of the Tifosi cheering when a McLaren passed a Ferrari. It must be remembered though that Prost was a confirmed Ferrari driver for 1990 while Berger, the hero of the 1988 race, was leaving the Scuderia to take Prost's seat at McLaren. The Williams' pair of Boutsen and Patrese, having found the limits of the older FW12 model, were circulating in 4th and 5th places but at no stage threatened the leaders.
On lap 44 the roar of the crowd told the story as the V10 Honda in Senna's McLaren comprehensively blew up going into the Parabolica, dumping its oil onto the rear tyres and sending Senna into a gentle spin and retirement, handing Prost the lead which he held to win his first Italian Grand Prix since 1985. Berger finished second for not only his first points of the season but indeed his first race finish while Boutsen came home third. Despite Prost's engine complaints, he still managed to set the fastest lap of the race on lap 43.
Prost's win restored his 20-point championship lead over Senna with only four races remaining in the season. However, due to the "Best 11" scoring system, Prost had now scored major points in 11 races while Senna could still score from all four remaining races. This meant that unless Prost won races, he would be able to score only a small number of points for the remainder of the season while Senna could conceivably score a maximum of 36 points (and win the championship) if he won the last four rounds.
McLaren-Honda won the Constructors' Championship with four races left.
Alain Prost 
