behind Senna, with Thierry Boutsen fourth in the second Williams. Drivers' Championship leader Alain Prost was fifth in the second McLaren, with Gerhard Berger sixth in the Ferrari. The top ten was completed by Alessandro Nannini in the Benetton, Stefano Modena in the Brabham, Derek Warwick in the Arrows and Pierluigi Martini in the Minardi. Nigel Mansell could only manage 12th in the second Ferrari, nearly seven-tenths behind teammate Berger and over two seconds behind Patrese, and later complained of traffic. Qualifying classification Race Race report At the start of the race, Patrese, Senna and Caffi maintained their grid order into turn 1, while Boutsen lost out to Prost as Berger passed both of them. Further back, Mansell made a good start, rising to 8th at the first corner. It soon became clear, however, that Caffi was struggling, the Dallara unable to replicate the speed it had shown in qualifying. Before long he had been passed by both Berger and Prost, and was holding up a train of cars consisting of Boutsen, Nannini, Mansell and Warwick. Nannini exited the train when he pulled in to change tyres. This promoted Mansell to 7th, which he quickly turned into 5th by passing Boutsen and Caffi in quick succession. He then set about closing the 17-second gap to the leaders, and was promoted to 4th when Berger pitted for tyres. Having caught up to the leading group, Mansell passed Prost for 3rd. Patrese's Williams then began to develop a problem with a holed radiator, which slowed him and bunched up the leading group. Eventually, Patrese's holed radiator became so bad that both Senna and Mansell were able to pass him in the space of a few corners. Patrese retired from the race shortly afterwards. Mansell now began to pressure Senna, clearly faster but unable to pass due to the extra power of the McLaren's Honda engine. Meanwhile, Prost pitted for tyres and rejoined 6th, while Berger only inherited 3rd briefly before he retired with gearbox problems, leaving Senna and Mansell on their own. Eventually, the pair came up to lap Stefan Johansson's Onyx. Senna caught him at an awkward moment, just at the accelerating zone out of turn 3. The Brazilian uncharacteristically hesitated, briefly lifting off, and this allowed Mansell to draw alongside as they went past Johansson and then use the Ferrari's greater momentum to surge past Senna and take the lead.