His chances of winning the Championship were over, but Nigel Mansell could never be accused of giving up a fight.
Qualifying for the Grand Prix of Portugal at Estoril was as close as any Grand Prix in history. Mansell took pole, a mere 0.02 seconds ahead of Prost, who put his Ferrari on the outside of the front row only 0.04 seconds ahead of third place man, Ayrton Senna! At the start, the Englishman got too much wheelspin and nearly took himself and his Ferrari teammate out of the race. He regained control, but not before Senna and Berger had stormed into the lead.
Mansell hounded Berger for second; he was all over the back of the McLaren but just couldn't get alongside. On lap 27, Mansell accidentally went wide and Prost slipped through. His tires were nearing their useful lives and he took the opportunity to head into the pits for a fresh set of rubber.
After the McLaren and Ferrari teams had stopped their cars for new tires, the order was Senna, Mansell, Berger and Prost. Nigel was flying now, taking more than a half-second a lap off the leader until he closed right up on the Brazilian. On lap 50 the Ferrari came down the straight so fast that Ayrton didn't have any hope of defending his position so he simply signaled the Ferrari to pass! On the next lap, anxious to build up a lead, Mansell punted Phillipe Alliot off the track! Thankfully, the Ferrari sustained no damage.
Mansell would go on unchallenged until the race was halted on lap 61 due to an accident. Prost was outwardly upset that Mansell had not been ordered to hold up Senna to setup a pass, but nothing can take away from Nigels spectacular drive on this day!
Undeniably quick at Estoril, Mansell passed Senna at two-thirds distance on his way to victory! Senna was only two seconds behind but never threatened Mansell's lead.