The 1988 Portuguese Grand Prix was a Formula One motor race held on 25 September 1988 at the Autódromo do Estoril, Estoril. The race, contested over 71 laps, was the thirteenth race of the 1988 Formula One season and was won by Alain Prost, driving a McLaren-Honda, with Ivan Capelli second in a March-Judd and Thierry Boutsen third in a Benetton-Ford. Prost's team-mate and Drivers' Championship rival, Ayrton Senna, could only manage sixth.
McLaren gained their 9th front row of the year with Alain Prost in front of Ayrton Senna for the first time since France. Prost, whose MP4/4 had a brand new, stiffer chassis, set his fastest time early in Saturday qualifying, and then confident that Senna couldn't better the time, spent the rest of qualifying lounging around the McLaren pit in jeans and T-shirt while Senna simply couldn't find a clear lap. They were ahead of Ivan Capelli in the atmospheric March-Judd. In fact, both Marches were in the top five, with Maurício Gugelmin in fifth behind the Ferrari of Monza winner Gerhard Berger. Both Capelli and Gugelmin expressed delight with their cars, especially in the fast corners and many saw them as a chance to upset the McLaren apple cart in the race.
After their impressive performance in Italy which resulted in a 3-4 finish for the team, the Arrows-Megatrons of Derek Warwick (10th) and Eddie Cheever (18th) struggled in Portugal. Both drivers complained of little grip on the rarely used Estoril circuit, which was compounded by slow turns which exposed the Straight-4 Megatron engine's famous lack of throttle response.
After missing the previous two races in Belgium and Italy due to illness, Nigel Mansell was back in his Williams-Judd. Other than complaints of a sore neck he never missed a beat and qualified a fine 6th, less than 0.1 behind Gugelmin, though he knew it would be a long race which would test his fitness.
Julian Bailey (Tyrrell-Ford), Stefano Modena (EuroBrun-Ford), and the Zakspeeds of Piercarlo Ghinzani and Bernd Schneider all failed to qualify while Oscar Larrauri (EuroBrun-Ford) failed to pre-qualify.
The first start was aborted when the Rial-Ford of Andrea de Cesaris stalled on the grid. The second start was aborted after Derek Warwick stalled his Arrows A10 and was hit by de Cesaris, with Luis Pérez-Sala (Minardi) and Satoru Nakajima (Lotus). Ayrton Senna led off at the third start, to the delight of the Portuguese crowd. At the start of lap 2, Alain Prost pulled out of Senna's slipstream to pass him. Senna moved violently over on Prost and forced him towards the pit wall at over 280 km/h (174 mph). The Frenchman nonetheless maintained his will to pass the Brazilian, not lifting off the throttle, and passed Senna into the first corner.
Prost was not impressed with Senna's tactics and this led to some strong, but controlled, words in the McLaren camp after the race (Senna countered Prost's anger by stating that he had almost been pushed onto the grass by Prost before the first corner after the start, though many saw this as a tactic used by almost all drivers, including Senna, at just about every start). Prost's lead built up to 7 seconds and would last until the flag, while Senna was being troubled by an erratic (and ultimately false) fuel readout which was telling him he was using too much. This allowed Capelli to close right up on him. On lap 22 the Italian out-braked Senna to excited acclaim and opened up a gap on him. It was the first time since Prost suffered from a severe misfire and poor handling from the start of the wet British Grand Prix (that ultimately led to an early retirement) that a McLaren had been passed on track by anything other than another McLaren. Soon after Gerhard Berger also passed the McLaren, leaving Senna exposed to the attacks of Nigel Mansell's Williams. The Briton was closer on the corners, but the Honda engine was superior in the fast sectors of the track.
Berger had claimed the fastest lap in his pursuit of Capelli, but spun off on lap 36. He had accidentally set off his fire extinguisher, with the resultant freezing of his leg with carbon dioxide causing his foot to slip off the pedals. Berger had been attempting a cockpit adjustment to his car but on the bumpy Estoril surface simply hit the wrong button. On lap 55, Mansell and Senna attempted to lap Jonathan Palmer: during this manoeuvre Mansell hit the back off the McLaren and spun into the barriers though without any damage to Senna who continued on. Maurício Gugelmin, Nelson Piquet, Michele Alboreto, Riccardo Patrese and Thierry Boutsen were hotly contesting the last point place in 6th. On lap 29 Patrese retired with a split radiator and the next lap Piquet retired with clutch and gearbox problems. On lap 57, Senna, still having problems with his fuel readout, pitted for a tyre change and was passed by Alboreto, Boutsen and Derek Warwick, falling to 6th.
Prost won convincing from a stunning Capelli; the gap at the line was just 9.5 seconds and Prost himself was marginal on fuel. Fuel problems were a notable feature of this race: on the very last corner of the race Alboreto's engine stuttered-his car was running out of fuel despite the gauge indicating he had plenty left. Boutsen passed him to get his 5th podium of the year and Warwick claimed 4th place. The dry Ferrari of Alboreto and McLaren of Senna were classified 5th and 6th.Bold Text indicates World Champions.
Note: Only the top five positions are included for both sets of standings. Points accurate at final declaration of results. The Benettons were subsequently disqualified from the Belgian Grand Prix and their points reallocated.