Following a late electrical failure that took him out of the running for a podium finish in Rio de Janeiro’s opening round, Senna arrived at Estoril looking for his first points of the season. Senna and Lotus had certainly showed flashes of pace-setting form in Brazil, but here he was able to unleash some fearsome speed from his Renault-powered 97T right from Friday’s first qualifying session. He beat McLaren’s Alain Prost to pole by 0.413s, and was 1.152s faster than teammate Elio de Angelis. De Angelis complained of tyre issues on Friday.

Senna said of his first-ever F1 pole: “I would like to be able to get away in the lead because then you are clear of any problems on the first lap. Then I will be able to see how fast I can go and pace myself accordingly. We tried the car with full tanks and it felt good, but there is no overall race plan, we shall have to wait and see what conditions are like.

“If everything is OK, I hope that I can win my first Grand Prix.”

On raceday, heavy rain drenched the track – and F1 was about to get another glimpse of Senna’s wet-weather skills that had come so close to earning him Monaco Grand Prix glory a year before. Could he reproduce that kind of performance? Senna made a perfect start, leaving Prost in his wake, as de Angelis powered through to second. Prost ran third, with Ferrari’s Michele Alboreto fourth. Keke Rosberg stalled at the start, amazingly without being collected by those behind, while Williams teammate Nigel Mansell spun on the warm-up lap and on the opening lap!

Portuguese Grand Prix winner: Ayrton Senna
Portuguese Grand Prix winner: Ayrton Senna

Despite never having tested this car in the wet, Senna led by 2.5s on the opening lap, and simply disappeared into the distance. Meantime, drivers were spinning off left, right and centre in the dreadful conditions. In his BBC TV commentary, former world champion James Hunt said: “With the talent that Senna showed in Monte Carlo last year in those dreadful conditions, when he absolutely threw the Toleman around with wonderful control, I don’t think it really matters what the Lotus is really like! He’s got such a prodigious talent.”

As Senna continued on his imperious way out front, de Angelis battled hard to keep Prost behind him. The rain intensified as the race progressed, and crashed cars had begun to litter the circuit as they failed to cope in the terrible conditions. Keke Rosberg shunted his Williams hard at the final corner, and the Williams was simply abandoned in the middle of the track for lap after lap until marshals finally shifted it. Senna began waving his arm to the officials, complaining that the heavy rain and standing water were too much to cope with. Proving how diabolical conditions were, Prost aquaplaned as he crossed the start/finish line, spinning and bouncing backwards into the barrier and out of the race.

“It was a hard, tactical race, corner by corner, lap by lap,” said Senna afterwards. “The big danger was that conditions changed all the time. It was difficult to keep the car in a straight line sometimes, and for sure the race should have been stopped. Once I nearly spun in front of the pits, like Prost, and I was lucky to stay on the road.”

By the time of Prost’s spin, Senna was already over 30s ahead of his opposition. Officials were keen to stretch the race distance to at least three-quarters, in order to award full points. In fact, it only had three laps trimmed from its planned duration by the time it hit the two-hour limit. In just his 17th Grand Prix start, Senna won the race by 1m02.978s from Alboreto, with the lapped Tambay completing the podium, as de Angelis faded back to fourth. As Senna crossed the finish line, Mansell went off behind him on to the grass.

“The car was sliding everywhere – it was very hard to keep [it] under control,” said the man who’d just claimed the first of his 41 Grand Prix victories. “You often saw cars sliding about all over the place purely through lack of grip and too much power. The only problem [I had] with the car was the brakes, but under these conditions you expect that.

“Once you were close to someone, you could not see anything. People think I made no mistakes, but that’s not true – I’ve no idea how many times I went off! Once I had all four wheels on the grass, totally out of control, and the car came back on the circuit.

“Everyone said ‘Fantastic car control’ but it was just luck.”

Senna’s joy at victory was unconfined, with seatbelts off and both hands waving in the air, and the image of him returning to parc ferme – greeted by his Lotus team manager Peter Warr and his mechanics, including Kenny Szymanski who was literally jumping for joy – is one of the all-time classics. When asked after the race what this first victory meant to him, he replied: “It means that all the years and all the effort I have put into motor racing, since [I was] four years old, are giving me something good back.”

At the opposing end of his Formula 1 career, it was often said that Senna’s victory in the European Grand Prix at Donington Park in 1993 was his greatest performance. The man himself disagreed: “No way! I had traction control.