It's another twist, but is this really the end of Tiger Wood's tale?

For many years he has been up there with presidents and movie stars as contender for most famous American on the planet – and unquestionably his country’s biggest global sports star, dominating his chosen field as no other. But has Tiger Woods now reached the end of the line?

The question can no longer be avoided after Woods’ announcement this week that he is taking indefinite leave from golf to try to repair a game that is in shreds.

“My play and scores are not acceptable,” he said – if anything an understatement after a round of 82, the worst of his career, at last month’s Phoenix Open, scarred by wild drives and fluffed chips, which left him tied for last place.

That was followed a few days later by withdrawal midway through the first round of his next scheduled tournament.

Back troubles were the reason, apparently unrelated to the disc surgery he underwent last year, or to four separate operations on his left knee since 2008. Now, we are told, he will not return until his game is “tournament ready”.

In his halcyon years Woods, terse, secretive and often dismissive at the best of times, inspired admiration, rather than love. But his recent travails have bred an unexpected affection. The Tiger has been revealed as human – and nothing is more excruciating than watching a great performer struggling in vain to recapture what was once second nature. Thus it was with Muhammad Ali in the twilight of his career. So it is now with Woods.

Pro golf is the cruellest sport. It does not offer the shelter of a team, within which the floundering player can seek anonymity. You are not playing an opponent: just the golf course and yourself, alone and visible to all.

Ever since he burst into the national consciousness when he won the 1997 Masters, Woods sailed above the problem. Simply put, he never struggled. But now his demons are not just physical but also – as his short game agonies show – surely mental as well.

It is hard to remember now the impact of that first major championship victory, almost 18 years ago.

Woods was only 21. He had turned pro just the year before. Yet he routed the field of the world’s finest golfers, winning by an unbelievable 12 clear strokes. The final round that Sunday afternoon at Augusta set a TV ratings record that still stands. Everyone realised that a new era for golf had begun.

Tiger’s race, of course, only added to the sensation. Unlike Ali or Jackie Robinson, who broke the colour barrier in major league baseball, he never portrayed himself, at least in public, as a symbol of black America. Back in 1997, he referred to himself as “Calbinasian,” to sum up his exotic mix of Caucasian, black, American-Indian and Asian ancestry. In the national mind, though, he was of course black.

A handful of African-American golfers had played on the tour since the PGA dropped its infamous “Caucasian clause” in 1961, even winning the odd event. But Woods was the first of them to reach the summit: the outsider who made a nonsense of golf’s country club ethos, and its image as bastion of the ruling white US establishment.

Like Ali and Robinson before him, and Barack Obama after him, Woods – whether he liked it or not – became a milestone of perceived racial progress in America. As such, he made Americans feel a little better about themselves.

His feats, and his background, also turned him into an unmatched money machine.For most of the 2000s, he was estimated to be the world’s highest-paid athlete, as he won tournament after tournament and sponsors paid fortunes for the blessing of his name. By 2009, according to Forbes magazine, he had become the first sports star to amass career earnings of $1bn.

But a few months later Woods’ world fell in, with the scandal that started with a bizarre car accident, metastasizing into reports of serial philandering and destroying his marriage.

Since then he has never been quite the same. For seven years he hasn’t added to his 14 majors, and the injuries have multiplied.

For a while recovery seemed possible, as he won five events in 2013 and regained golf’s No 1 ranking. But the old intimidation factor, which turned opponents into losers even before they had teed off, had already vanished.

A younger generation, led by Rory McIlroy, has no fear. Woods’ world ranking has tumbled to 62 – and on current form that’s flattering. So is this the end?

Never, ever, write off a player of his calibre and singlemindedness. “I expect to be playing again very soon,” he declared, perhaps as soon as later this month.

A more revealing target date is the Masters, in seven weeks’ time. In the meantime, Woods has turned 39. That’s not old by normal golfing standards (Jack Nicklaus won his last major at 46), but for a player whose body has borne so much, twilight is surely approaching.

To return to the top now, in a ferociously competitive sport, would be among history’s greatest comebacks.

Sheer pride alone makes it hard to imagine the Tiger continuing to struggle, an ever-devalued scalp on the tour he once dominated.

But whenever he calls it a day, he will be missed: not just by golf, but by anyone who ever wanted to witness the truly exceptional.