Race report
The weather on Sunday morning was very poor, with heavy rain. The first start was aborted after Berger stalled his engine on the grid, meaning the intended 70 laps race distance was reduced to 69. The rain began to recede, and Mansell, Nannini and Sala elected to pit for slick tyres at the end of the second formation lap, and start from the pit lane. [3] However, with apparently no guidance from pit lane marshals or lights, Mansell and Nannini changed their tyres and left the pit lane to rejoin the circuit 17 seconds before the starting procedure had been completed and the green lights were shown to the rest of the field. [2] Both cars circulated ahead of the pack for a few laps until they were caught by the leaders and then black-flagged, i.e. disqualified, for starting the race too early.
At the start the rest of the field got away cleanly, except for Modena and Martini, who collided and both retired. Alboreto pitted his Tyrrell to retire with electrical problems. Prost led from Senna, Patrese, Berger, Boutsen, de Cesaris and Alliot, who had made a strong start. At the end of the lap Prost and Caffi pitted for slick tyres. On the following lap Prost entered the pits again, and retired there with front suspension failure. This left Senna leading as Boutsen passed Berger for third, and the order changed several times over the next few laps as drivers pitted for dry tyres, although the rain soon returned. Cheever retired from eighth position with an electrical fault. Senna was one of those to pit on lap four, and dropped to fifth, leaving Patrese in the lead from Boutsen, Berger and Alliot. Berger repassed Boutsen for second place, but immediately retired with a broken alternator belt. Designer John Barnard later said, "It isn't the actual gearbox that gives trouble. It's the electrical ancillaries which keep packing up." [2] Further back, Tarquini spun out of the race, having just passed Arnoux for eighth place.
Senna passed Alliot for third, behind the two Williams cars of Patrese and Boutsen. This order continued until lap 11, with Warwick fifth, ahead of Larini, Arnoux, Danner, Capelli and Sala. Next were the two Dallaras of Caffi and de Cesaris, followed by Palmer, Piquet and Gugelmin. The last two runners, Moreno and Johansson, had already been lapped.
On lap 11, Boutsen and Capelli pitted, and on the next lap Gugelmin dropped out with electrical problems, while Sala crashed his Minardi into the barriers having inherited eighth place. At the back, Johansson pitted his Onyx for a second time, but emerged dragging a tyre gun, air line and part of the metal pit gantry on to the track. He was shown the black flag, but later claimed not to have seen it, and was disqualified for ignoring it. [2] [3]
On lap 14, Warwick passed Alliot to move into fourth place, while both Dallaras passed Danner, who dropped to ninth. On lap 15, Larini also passed Alliot, while the Dallaras both passed Arnoux. Boutsen passed Danner and then Arnoux, moving up to eighth. On lap 17, Alliot pitted from fifth, while the Dallaras passed Larini's Osella. Piquet overtook Palmer for 11th. The order at the end of lap 18 was Patrese, Senna, Warwick, Caffi, de Cesaris, Larini, Boutsen, Arnoux, Danner, Piquet, Palmer and Alliot, with Capelli and Moreno a lap adrift.
Boutsen pitted his Williams again, finding that slick tyres were not the correct choice. Senna was also still on slick tyres at this stage of the race, and was struggling for traction on the wet parts of the circuit. On lap 21 he pitted for wet tyres and dropped to sixth. De Cesaris and Larini passed Caffi, and further back, Alliot started moving back through the field, passing Palmer and Piquet. On lap 22, Larini passed de Cesaris, taking the Osella into third place. Both Dallaras then pitted, allowing Senna back up to fourth place.
Alliot passed Danner and was up to sixth place in the Lola when he spun out of the race on lap 27. Two laps later, Capelli spun out of 12th place. Boutsen moved up a couple of places to fifth, passing Danner and Arnoux again, while Senna finally caught and passed Larini for third. Palmer overtook Danner for eighth place. On lap 34, Larini's Osella failed with electrical problems with the Italian still running strongly in fourth place. Patrese had been on wet tyres since the start, and he finally pitted to change them on lap 35, leaving Warwick, also still on wets, to take the lead of the race in the Arrows. Palmer then crashed out from seventh place in the sole remaining Tyrrell, having secured what would be the fastest lap of the race. [2] It proved to be the only fastest lap of Palmer's career.
Senna caught Warwick after the British driver had led for four laps, and passed him on lap 39. Warwick dropped out of the race from second place on the following lap, with engine failure. Piquet passed Arnoux to move up to fifth place. There followed a period of relative stability, with only nine cars left circulating, with 28 laps remaining. Senna led from Patrese and Boutsen, with de Cesaris fourth, ahead of Piquet, Arnoux, Danner, Caffi and Moreno. Danner and Caffi both spun several times and had been lapped more than once, as had Moreno, who lost a front wheel and drove back to the pits on three wheels for a replacement. Caffi passed Danner for seventh on lap 50, and Moreno finally dropped out with differential failure after completing 57 laps.
On lap 63, Patrese and Boutsen came up behind Piquet, who was lapping Danner's Rial. Boutsen took his chance and overtook his team-mate for second place before they lapped Danner. Patrese had been losing downforce and grip due to a loose diffuser on the rear of his car. [3] By this time, only Senna and the two Williams cars were on the lead lap. Then on lap 67, with Senna comfortably ahead, the V10 Honda engine in his McLaren failed, and he pulled on to the infield just after the start-finish line to retire.
Boutsen inherited the lead, and led the last three laps to beat his team-mate Patrese by just over thirty seconds. De Cesaris and Piquet, having unlapped themselves with Senna's retirement, finished third and fourth. Arnoux was fifth in the Ligier, with Caffi a further lap down in sixth, both Dallaras finishing in the points. Senna was classified seventh ahead of Danner eighth, the last surviving runner, three laps adrift. Boutsen later said, "I couldn't believe my eyes when I saw the 'P1' sign, and I drove very carefully for the rest of the race." [2]
It was Boutsen's first Grand Prix victory (and the first victory for a Belgian driver since the 1972 German Grand Prix with Jacky Ickx), and Patrese's third successive second-place finish. It was Dallara's first podium finish, and the only time both their cars finished in the points. It proved to be the last podium finish for de Cesaris, and the last points finish for Arnoux. It also proved to be Christian Danner's last race in Formula One, as he failed to qualify for any further Grands Prix before Rial left the sport at the end of the season.
Jonathan Palmer 
