So they came to Estoril, the four of them, with the world championship beckoning. And, truth be told, the heavy money was on Piquet, the man who had won three of the last four, who had the psychological momentum riding with his. During practice, though, it was Mansell who impressed. With a spare car to work with, Nigel was solidly there, beaten to the pole only by Senna.
On Sunday his game plan was well ordered and simple: he was aiming to lead all the way. And he did exactly that. Senna and Piquet were left to fight over second - which went to Prost, after Nelson had made a mistake, and Ayrton ran out of fuel. Nigel simply drove away from them, facing pressure only from himself.
Three days before practice began at Estoril, Nelson Piquet was at Silverstone, testing new 'periscope' turbo air inlets on the Williams-Honda. And some indication of the quantum stride taken by the grand prix car in the last year or so may be gleaned from his lap times. You may remember Keke Rosberg's mesmeric pole position lap at last year's British Grand Prix: in the Williams FW10 he alone got into the 'fives'.