LONDON, England - While Formula 1 and the whole motor-racing world remembers Ayrton Senna on the 20th anniversary of his death at Imola happier memories of another race, 10 years earlier, highlight why the great Brazilian is still so sorely missed.The 1984 Monaco Formula 1 GP, held in pouring rain, was when even the sleepiest followers of the sport woke up to the talent that had come into their midst.Senna, starting 13th in the first street race of his rookie season and in a car that he had failed to qualify two races earlier at Imola, finished second to McLaren's Alain Prost - his future team mate and rival - for his first F1 step on to the prizewinners' podium.SURREAL EXPERIENCEThe harder the rain came down, the quicker he went. The Brazilian set the fastest lap and was poised to take the lead when the race was stopped, controversially, and half points awarded.Pat Symonds, now technical head at Williams after working with Michael Schumacher at Benetton and Fernando Alonso at Renault, was Senna's race engineer that day at the unheralded Toleman team. He looks back on it as an almost surreal experience..."It wasn't exactly on the radar," the Briton told Reuters. "It wasn't like 'Yeah, this is coming, we're going to win one soon'. It was like 'Wow!'. Everything aligned and we very nearly won the race."It was very surreal and there were very mixed emotions afterwards, having achieved something more than either of us had achieved before and yet not got that ultimate prize."There was the initial euphoria of second place and then, two hours later, thinking 'Well, actually, it should have been first'. That was quite hard to deal with."DOMINATED FORMULA FORD 2000Senna had been a sensation through the junior series, winning Formula Ford championships and 12 out of 17 races in his first year in England in 1981.In 1982 he had dominated Formula Ford 2000 and then won the British Formula 3 title in 1983 (after a battle with Martin Brundle) and the Macau GP.'Other drivers? He just thought they were there to be beaten' - SymondsBrazilian Senna had tested with various teams, among them Williams and McLaren, the latter the team for which he would win his three Drivers' titles, before he signed for Toleman. But it was at Monaco was where many people sat up and took notice.McLaren head Ron Dennis told reporters in a recent recollection of their time together: "Probably the first time that I really noticed him was his driving with wets, when he was driving that awful-looking car, the Toleman, in Monte Carlo."If the race had finished, who knows whether Prost would have let Ayrton past, but what he was doing was spectacular. And such a rubbish car, too."ABSOLUTE TREASUREEven Symonds, who had come through Formula Ford and seen for himself how impressive Senna was in the junior ranks, was surprised. "I knew the guy was good. When he joined Toleman I thought we'd done very well."Then he added: "I won't for one minute pretend really to have anticipated how well we'd done and what an absolute treasure we'd got. I think a great sign of a good driver is that you forget they are inexperienced... and that was the case with Ayrton."He was just so at home in F1 that you forgot he was a rookie."Whether Senna would actually have won in Monaco that afternoon had the race gone full distance is one of F1's many unanswered questions. It emerged later that the Brazilian's car was damaged, so Pat Symonds suspects he might have done. He said:"Yes, it is true that one of the front rockers was cracked. We believed that had happened on a trip over the kerbs at the chicane but nobody will ever know whether the car would have finished."In my view it was a serious crack but it wasn't just about to fail. Nobody will ever know the answer."BRILLIANCE - AND FAILINGSWhat is certain is that Senna showed that day some of the qualities that would make him such a formidable competitor - complete self-confidence and an amazing ability to absorb information.Senna left Toleman for Lotus at the end of that year and won his first race in Portugal in 1985.His brilliance, and failings, would shine through - the win in the wet at Donington Park in 1993 ranks among his greatest - but Monaco was to become a favourite with the Brazilian; he won six times there.Symonds recalled: "There were so many drivers who, to drive a car fast, needed 100% of their mental capacity. Ayrton didn't. He could drive it faster than anybody else and he still had capacity to remember every little detail of every lap."We didn't have data acquisition in those days, we didn't have real-time telemetry. It was down to the driver. And he was very, very good at describing the car and remembering every little thing that happened."He was naturally very competitive, he had this self-belief that wasn't arrogance. It was true self-belief. Therefore he didn't have that reverence for established drivers of the time."He just thought they were there to be beaten."