Back in July 1986, on a rather special Monday at Royal Dublin, I remember marvelling at the sight of Jack Nicklaus actually hitting golf shots on Irish soil, in an exhibition match with Seve Ballesteros. Only three months previously, at 46, he had won the US Masters for a sixth time, further proof, were it needed, of his uniqueness in the game.

There was a temptation to think of him as indestructible, while any thought that his record of 18 major professional championship triumphs might be challenged, much less surpassed, seemed ludicrous.

Now, 14 years on, and with his all-time supremacy under undoubted threat from Tiger Woods, the Bear is set to bid farewell to the Open at St Andrews.

Last month, at Pebble Beach, there were tears from the great man when he made what was assumed to be his final journey up the 18th hole of a US Open. And there is no reason to believe that the events of this weekend will be any different. Quite apart from its aesthetic beauty, his love of Pebble was entirely understandable for the milestones it marked in his career. It was where he captured the US Amateur for a second time in 1961 and, 11 years later, it was the scene of his third US Open triumph, which allowed him to tie the 13 major championship titles achieved by Bobby Jones.

But of St Andrews, he has been moved to say: "I would go so far as to describe the Old Course as the most intriguing and demanding challenge in the whole game."

So, there was enormous satisfaction for him in capturing the British Open on the Old Course on two occasions. The first came in 1970, when the hapless Doug Sanders squandered victory by missing a putt of no more than three feet on the 72nd hole. And the second was in 1978, when the young New Zealander, Simon Owen, wilted within site of the finishing line under the forbidding presence of the Bear.

Yes, there will be tears this weekend. And many of them will be shed by lovers of the Royal and Ancient game who were privileged to savour these great moments and his earlier, breakthrough triumph at Muirfield in 1966. They will think of the innate dignity of a truly great sportsman, who could be fiercely competitive yet wonderfully caring to his rivals.

He is the player who, when asked what separates a major champion from a great golfer, replied: "Basically, it all comes down to management of oneself."

"There were plenty of players who could play as well as I did, when I was playing well," he explained, "but there were only one or two fellas I have to worry about from a management standpoint.

"I managed to separate myself from the herd by the way I enjoyed competition. I enjoyed getting myself into contention, which probably explains why I was always a bit cautious in the first two rounds.

"If you've got 72 holes to play, it's a long way to the finish. After you've played halfway, and you're three or four under par, you've only got a few guys to worry about. It sort of almost becomes a matchplay game from then on."

The natural conservatism of Nicklaus caused him to marvel at the manner in which Woods positively crushed the opposition when winning by 15 strokes at Pebble. "I was prepared to do just enough to win by two or three, whereas Tiger seems determined to kill the other guys," he said. "I find that very interesting."

During his visit to Limerick last week, Woods agreed with that assessment by the Bear. But he questioned whether Nicklaus actually set out to do things that way. "I know Jack said those things publicly, but that's not what he said to me," the world number one claimed, with a knowing smile.

Though Nicklaus made an undistinguished British Open debut at Troon in 1962, when he started with an 80 and eventually finished in a share of 34th place behind Arnold Palmer, it was the experience of St Andrews two years later which changed his perception of the challenge.

"For an American, St Andrews is particularly difficult and perplexing because it does not look or feel like a golf course at all," he said. "There is nothing visually or architecturally like it."

But on his first visit there in 1964, he developed what was to become a much-copied technique of picking out a spot a yard in front of his ball and checking his alignment off it. "Until that day, I used to be like everyone else and pick out a spot in the distance, maybe a church spire, or a tree-top," he said.

"At St Andrews, this is not possible, because there are few church spires in the distance and no treetops. So I decided to align myself from something a yard in front of me and, when I thought about it later, it made a lot more sense anyway." Typically, he learned fast. In fact his debut appearance on the Old Course was marked by a second-place finish behind Tony Lema who, it has to be said, achieved a remarkable triumph in that he was forced to play the course blind, having arrived from a tournament in the US too late for a practice round.

Two years later, the Bear won the Open for the first time. And his victory at Muirfield was recorded beautifully by the inimitable Pat Ward-Thomas of the Guardian, who wrote of Nicklaus joining the "Olympians of golf".

"His victory by one stroke from the most gallant challengers in Sanders and (Dave) Thomas, completed for him the modern quadrilateral of supremacy. In all history, Hogan, Player and Sarazen alone have won the American and British Opens, the Masters and the United States PGA Championships, and Nicklaus was only 26 in January of this year."

Dare we suggest that Woods would be only 24 if he achieves the same distinction by capturing the Open next Sunday?

In the event, when the Open returned to the Old Course in 1970, there was the sight on the 72nd hole of Sanders bending down to pick up an imagined speck on the line of his three-footer. Then, instead of marking the ball and stepping away from it to compose himself, he elected to finish out the hole . . . and pushed the left-to-right putt right of the target.

Years later, Sanders would admit: "I made the mistake of not letting Trevino (his playing partner) putt first. I made the mistake of thinking which section of the crowd I was going to bow to. It was all my fault. There was only one person to blame - Doug Sanders."

The ultimate irony came in the play-off the following day. Playing a perfect, running shot to the 18th, Sanders birdied it. But Nicklaus, who had stood on the tee with a one-stroke lead, also made three to secure victory. It was the occasion when the Bear, in what would be interpreted nowadays as a blatant act of intimidation, peeled off his bright-yellow sweater on the 18th tee.

Having toyed initially with the notion of hitting a three-wood downwind, he eventually smashed a driver which ran through the back of the green, only a few feet from the out of bounds. But he chipped and putted for a winning three.

Of the Bear's third Open triumph in 1978, Ward-Thomas wrote: "Once again, St Andrews has been the place of destiny for Jack Nicklaus. His victory was as if the gods, as in 1970, having made him do penance for three lean years, relented and rewarded him in the golfing place closest to his heart. Not since James Braid in 1910 has any golfer won the Open twice on the Old Course."

The Guardian's man concluded: "Nicklaus is an uncommon human being and golf has been blessed that he should remain its foremost figure for so long. When, in the lovely evening sunshine, the vast throng gathered around the timeless setting, and thundered their applause for his triumph, they were acclaiming not only a great champion but a man they had taken to their hearts."

The win was significant for other reasons, notably as it marked his 15th major professional victory and the third time he had completed the Grand Slam cycle. And having won two tour events in each of 17 successive years as a professional, there were no arguments when he was named Sportsman of the Year by Sports Illustrated.

After Nicklaus had won the US Masters for a fifth time, Jim Murray, the celebrated columnist of the Los Angeles Times, wrote: "You can now, if you will, go to the blackboard and write 100 times, `Jack Nicklaus is the greatest golfer in the world'." And the magazine Golf World suggested: "Maybe next year we should start naming the secondbest player of the year. Nicklaus doesn't need the exposure any more."

In a way, that is what he has decided for himself, by declaring this to be his Open swansong. And with Woods aiming to become the youngest winner of the Grand Slam, it could be viewed as simply another example of the cyclical nature of sport.

But the normal rules have never applied to Nicklaus. Which will make it all the more difficult for us to say goodbye.