Senna pitted because of handling trouble and so Prost went into the lead and when he stopped for new tyres Boutsen briefly led before Piquet went back into the lead before his second stop. Prost then went ahead again and led for the rest of the afternoon, never looking threatened as he did not have a third tire stop while his rivals Senna and Piquet did. Mansell's race was disrupted by a puncture while Senna went out with engine failure and so Prost came home to win ahead of Piquet, Johansson, Berger, Boutsen and Mansell. After the season-opening race in Brazil there was a three-week gap during which March finished building the first 871 chassis for Capelli. Osella expanded to two cars with the second being run by a youngster called Gabriele Tarquini, while Brundle had the first of Zakspeed's new 871 chassis. Ligier was back in action with Megatron-engined cars for Rene Arnoux and Piercarlo Ghinzani. In addition there was another new team in the form of Gerard Larrousse's Lola-Ford/Cosworth team which had employed Philippe Alliot. But come the San Marino Grand Prix held at the fast Autodromo Dino Ferrari in Italy, Nelson Piquet had a huge accident at the flat out Tamburello corner when he suffered a tire failure during qualifying and was forbidden from racing by F1 doctor Sid Watkins. Goodyear decided that in the interests of safety it would fly in new tyres overnight for Saturday qualifying. On Saturday afternoon Ayrton Senna took pole position in his Lotus-Honda with Nigel Mansell second quickest in his Williams-Honda. The second row featured Teo Fabi (Benetton-Ford) and Alain Prost (McLaren-TAG) with the Ferraris of Michele Alboreto and Gerhard Berger together on the third row. The top 10 was completed by Stefan Johansson (McLaren), Riccardo Patrese (Brabham-BMW) and the two Arrows-Megatrons of Derek Warwick and Eddie Cheever. Senna led from the start but on the second lap at Tosa, Mansell swept into the lead and began to pull away. On Lap 6 Prost found a way ahead of Senna and then clawed his way up behind Mansell and stayed there. Prost's race ended, however, on Lap 15 when the McLaren suffered an alternator failure.