It was the roar Jack Nicklaus will remember most.

A long, throaty, sustained rumble of affection, so loud that truly it might have alerted shipping off the Firth of Forth as Nicklaus walked up the 18th green at St Andrews to complete the last competitive round of his career.

And when the last putt dropped, an eight-footer which was studied earnestly in that famous crouched style and which just happened to be the 1,126th stroke of Nicklaus' Open career, appropriately it was a birdie.

Only someone with a heart of stone could fail to have been moved by what happened next.

Nicklaus turned to each corner of a gallery, estimated at 20,000 and which had balconies creaking their appreciation, raised his arms and blew kisses to the crowd.

He held his son and caddie Steve in a huge bear-hug and yards away, on the most famous steps in golf, players, some 40 or so including Sergio Garcia, Vijay Singh and countless Americans, applauded until their hands hurt.

There was royalty too, Prince Andrew joining in the acclaim for a man who arguably has done more than any single sportsman for his sport. Nicklaus' wife Barbara, who is perhaps at long last going to see a little more of her husband, was there too.

There was a tear in Jack's eye, how could there not have been with so much emotion flowing these past two days under the famous Swilken Bridge, on which he stood for a last historic photograph.

So much so that for the past two mornings the queue had stretched 200 yards or more at the St Andrews branch of the Royal Bank of Scotland for £5 notes bearing the Nicklaus image, the first time a living soul, other than the Queen and the Queen Mother, had been recognised in such a way.

One woman, with the Nicklaus farewell fever building, had been heard to say ''I'll have three, how much are they?''

Those present certainly received their money's worth this afternoon as the largest gallery of this week, or possibly any week, craned to get a glimpse of the great man in action for the last time.

Of course, the 65-year-old pensioner with the artificial hip who recorded a level-par 72 in his last round for a three-over par tournament total which narrowly missed the cut, was not the dynamic force of yesteryear.

But he tried to give them one last glimpse of his greatness - a birdie at the par-five fifth, a brilliant pitch in to the par-four tenth for another.

The deep St Andrews pot bunkers, however, have no respect for reputations and Nicklaus was forced to play sideways at the 12th, resulting in his second bogey.

Nicklaus of old would never have spurned the four-foot birdie opportunity on 14, but if his aim was not always precise then there was as much graft in this last round as any before, including the two which clinched him this tournament three times, twice at St Andrews.

He also won four US Opens, six US Masters and five USPGAs.

No other golfer comes close to matching his major tally of 18, although victory for Tiger Woods on Sunday would take him to ten.

As Nicklaus soaked in the acclaim on that walk up the 18th fairway what memories must have flitted through his mind.

Of the time he and Arnold Palmer brought golf to a global television audience amid a decade when the Beatles changed the face of modern culture and man walked on the moon.

In those early days an arrogant Nicklaus, who once brazenly kept Ben Hogan and Sam Snead waiting on the tee, was not always the perfect ambassador with his brash manner and savage crew cut.

He had the wisdom, however, to temper that public image, so much so that he became one of sport's greatest ambassadors.

The putt he conceded to Tony Jacklin in the 1969 Ryder Cup, when a miss would have won the match for the United States, is one of sport's finest displays of sportsmanship.

His own putting, at its peak, was about as perfect as that nerve-fraying discipline can get, as demonstrated in his last major win, the US Masters at the age of 46, when he shot a final-round 65, making seven birdies in ten holes.

No wonder Bobby Jones was once moved to remark that Nicklaus played a game ''with which I am not familiar".

Why is he retiring from competitive tournaments when others might still want to enjoy the odd cameo performance?

Simple. The realisation that he can no longer enter a mainline tournament with a chance of winning.

It gnaws at his competitive soul. So much so that he might not have been too impressed when, after teeing off today, the group having just played the 18th, Nick Price, Chris Di Marco and Henrik Stenson, walked across to shake his hand.

He had 18 holes to play, a cut to make. It was no time for nostalgia.

That was what he wanted to believe. Even Nicklaus, however, who began the day at three over par, knew this was likely to be his last round.

And by the time that last putt dropped and the St Andrews clock with the golden roman numerals struck exactly 6 o'clock, time had been called on the greatest career in golfing history. But one thing is certain, he will hear that roar in his dreams forever more.