Richard Williams profiles a modern-day cricket legend who appears to have pressed the self-destruct button

For the past 10 years, Shane Warne has been that rarest of sporting phenomena: the cricketer you would take your children to watch, knowing that in middle age they will gratefully summon up a memory of the blond streaks, the smear of white sun-block, the gold earring and the flared flannels of the greatest spin bowler in the history of the game.

But now, at least to judge by the results from the first urine sample taken in Sydney on January 25th, Warne has joined the ever-growing list of sports heroes who have stained their reputations by taking drugs.

He offered an immediate explanation for the existence of a banned diuretic in his bloodstream. His mother, he said, gave him a fluid pill that morning, before Australia went out to play England.

He had never, he said, taken a performance-enhancing drug in his life. And, of course, there remains the question of analysis of the B sample, which will either confirm or overturn the initial finding.

A few years ago there would have been an instinctive desire to take a cricketer at his word and to write off the affair as an inadvertent transgression.

But those who follow sport long ago learnt the painful lesson that no one, even when apprehended with a needle hanging from their arm, ever admits to having taken drugs in order to improve their performance. It was always a mistake, a mix-up, an honest misunderstanding.

And so, sometimes, it may have been. The problem is that there is no longer any way to tell for sure. It would be nice to believe Shane Warne's explanation because his wonderful talent has done a great deal to revive the game of cricket, because he seems a good sort who refuses to take himself too seriously, and because his newspaper column yesterday morning, published only an hour or two before the news broke, began with the words: "My third and final World Cup begins today and I am desperate to make an impression."

No one in the long history of international cricket ever made a more immediate impression than Warne, who announced his arrival with his first ball in a Test match in England by clean bowling Mike Gatting.

Those of us who were at Old Trafford that day in June 1993 were immediately convinced that we had witnessed nothing less than the best delivery of all time. As the ball dipped in flight, pitched outside the leg stump and zipped across the batsman's body to hit the top of the off stump, Gatting's bafflement told its own story.

This was no fluke. Warne was the real thing, a slow bowler whose artistry made him at least the equal of Clarrie Grimmett and "Tiger" O'Reilly, the legendary Aussie leg-spinners of the pre-war era. Here was a 23-year-old who very obviously belonged to the modern age - the hair, the earring, the larrikin attitude - but who had ancient mysteries at his finger tips, plus a few new ones. It was the unlikeliest and most welcome of all cricket stories.

Warne represented a modern legend in the making, but his progress was often interrupted by misadventure. In adolescence he was expelled from the Australian academy for young cricketers.

Later an unwise telephone call to a girl while he was on tour in England made a juicy story for the tabloids and ended his marriage. His tendency to pudginess became the subject of jokes. He had barely reached his mid-20s when he began to suffer injuries to his right shoulder, followed by major surgery to his spinning finger. And last December 15th there was sadness all around the cricket world when he lay in agony at the Melbourne cricket ground after dislocating his shoulder while diving to stop a ball in the field.

At the start of his career, few expected Warne to be anything other than a shooting star. But after promising to burn out on many occasions, he lasted long enough to be named one of Wisden's five cricketers of the 20th century. And he may yet confound today's gloomiest predictions.