Amid the thrashing and splashing of the final training session in Seville yesterday, a calm descended at the pool as a tall, lean figure walked awkwardly over towards the water, slowly bent down, and washed his goggles.

Alex Popov paid little attention to the staring swimmers and pressmen around him, clamped his goggles to his face and, once a gap appeared in the lane in front of him, leaned forward and disappeared beneath the surface of the water. A moment later and the gawky Russian was transformed, gliding through the backwash. If there was any effort involved, it was difficult to perceive. Where before, on the pool deck, he was awkward and ill at ease, now Popov was in his element.

Power through grace. It is said that Popov learnt much about his slow stroking technique, his "feel" for the water, from swimming with dolphins in the ocean off Australia, where he is based for half the year.

Some coaches reckoned Popov is the closest man has come to a fish - "all he needs is gills," said one who has watched him spending six hours a day in the pool of the Australian Institute of Sport in Canberra. "It was a beautiful, unbelievable feeling," Popov said after his coaching session with the dolphins. "Mother Nature is so clever. She gives everyone their own shape, their own opportunities." Popov has certainly taken his opportunities well. Yet beyond the poolside, the fame of the world's fastest man in the water is fleeting.

Compare the way the track sprinter Michael Johnson's double gold achievements in Atlanta were heralded with the near anonymity of Popov. Yet to achieve a 50 and 100 metres Olympic freestyle double in Atlanta, Popov did not require any changes to the timetable (as Johnson did), and his achievement was doubly remarkable, since it was a repeat of his golden haul in Barcelona four years before. This past week, Popov has been saying that beating the Americans in their own backyard in Atlanta was the greatest challenge in his life, but many observers think the coming week could be tougher.

That is because no one under-estimates the effects of the round scar, twice the size of a 50p piece, tucked under his ribs, the legacy of a knife fight in a Moscow street last August. The knife damaged Popov's kidneys and diaphram, and scraped his lung. It took a three-hour emergency operation to save his life, something which also left him scarred, from his naval to his sternum.

Popov makes light of the incident now. "My soul was not damaged," he says. "I don't think the accident is going to affect my results." When he competes in the 100 metres freestyle on Thursday, we will find out for sure.

If Popov learned about his shape in the water from the dolphins, then he learned about racing in a masterclass from the last great swimming legend, Mark Spitz. Seven golds, including the Blue Riband 100 metres free, at the Munich Olympics testify that Spitz knew a thing or two about racing. When Spitz met Popov during a two-week training camp in 1991, the young Russian had yet to establish himself as a world beater.

"But I could see that this guy had tremendous potential," Spitz said, oblivious to the tales of the eight-year-old Popov screaming in terror at the water when taken to the municipal pool in Sverlovsk, his home town in the Urals, for his first lessons. Evidently, Popov eventually took to water well, so much so that the gangling, 6ft 7in tall swimmer now says he only feels at home when totally immersed.

The thing is, every swimming expert agrees, "he's a mechanical genius when it comes to stroke technique." Spitz says: "That's what they claimed I was good at, and I see myself in him."

Yet Popov has moved into a different era, rendering Spitz's times of a quarter century ago antique (Popov's 48.21 seconds 100 metres freestyle world record put 1972 vintage Spitz wallowing in his wake, 10 metres back).

The question to be answered this week is whether Popov is able to move into the new era himself. Much has changed in his life since the stabbing a year ago. He has married a Russian team-mate Daria Shmeleyva, and they are expecting their first child this year. Popov has been baptised into the Russian Orthodox church. In the water, Popov has been beaten in his warm-up races, and unusually he comes into the European championships with others ranked ahead of him.

On Thursday, we will discover whether the man who swims with dolphins still has power through grace.