He is unquestionably the ironman of the water, the most focused of men. But only an accident of birth helped make Steve Redgrave Britain's greatest ever Olympian.

Nobody could deny the 38-year-old Marlow man mountain dedicated himself to reaching a physical, technical and mental peak and then showed the mark of the truly majestic by staying there.

Redgrave is the builder's son product of Marlow Comprehensive, ill at ease in the Oxbridge haunts of the bright young things who have traditionally represented the public face of British rowing.

If he had been born 50 miles north or south of the quiet Buckinghamshire town on the banks of the River Thames it is doubtful he would ever have seen a shell, let alone broken the hearts of so many rival oarsmen across the world.

But he was, he did and, with victory in the coxless four alongside Matthew Pinsent, Tim Foster and James Cracknell, he won an incredible fifth Olympic rowing gold in Sydney.

Redgrave's achievement is one unrivalled in endurance sport. Only Aladar Gerevich, with six successive golds in the Hungarian sabre team at the beginning of the last century, has achieved more.

Redgrave's 6ft 4in frame is impressive, but his mental attitude has been just as important. "When I get in it (the boat) I'm in my element," he says. "I know what I'm doing. I know the score.

"Deep down, you know that when you're in the Olympic final rowing side by side with whoever there's no way they're going to beat you. That's the frame of mind you must get yourself into."

The dedication was already there from the age of 16, when he devoted himself to rowing, although originally as a sculler.

"Everyone told me I would be world champion and I kind of believed it," he once said.

"In 1978 I told my then girlfriend I was going to three Games."

The first was supposed to be in Moscow, which he missed because of a lack of funding.

Only in the build-up to the Los Angeles Games was he persuaded to turn his mind to pulling one blade rather than two as the stroke of the coxless four that edged out the United States to take gold.

Another member of that crew was Andy Holmes, and when after a further year as a specialist sculler Redgrave teamed up with him again it was to glorious effect as they became coxed pair world champions.

The following year brought more success, the pair doubling up in the coxless event and winning it while only narrowly surrendering their other crown.

Then came Seoul in 1988, a second Olympic gold for both in the coxless event and a coxed pair bronze.

Redgrave could have been lost to rowing at that stage. He turned from water to ice as he nearly made the British bobsleigh team and, with his new partnership with Simon Berrisford failing to hit the heights, others may have looked elsewhere.

But along came Pinsent - Eton and Oxford, the son of a rector, just 19, and everything Redgrave was not. They hit it off at once, despite Pinsent's initial fears. "I wasn't keen because it was a chance to screw up," he recalled.

But there were no such problems - and although the scratch pairing took bronze in the world championships in Tasmania in 1990 they realised the potential was there, especially when Jurgen Grobler arrived from East Germany to take charge of their coaching arrangements.

By 1991, their rivals were 10 seconds slower and nothing could stop them. They struck gold again in Barcelona in 1992 - in the coxed pairs with Garry Herbert - and again in 1996 in the coxless pairs in Atlanta.

After that triumph Redgrave famously said: "I hereby give permission to anybody who catches me in a boat again to shoot me."

But his enthusiasm was soon rekindled and, despite battling diabetes and debilitating bouts of colitis for the past four years, he and crew-mates Pinsent, Cracknell and Foster delivered gold for Britain in Sydney.

However, yesterday Redgrave revealed he was walking away from competitive action - and this time there is no going back.