The swing, always characteristically short, was now no more than a flick. But the old, professional hand-action was very much in evidence as Doug Sanders played the opening hole at Grange. After pitching to three feet, he called to his playing partner: "Throw it back, Christy. You know I've never missed one that long."
They laughed. Then O'Connor gently insisted that everything had to be in the hole, since they were playing a competitive round. Sanders duly sank the putt for an opening par.
He had travelled here last week to receive the Legends in Golf Award from the society of that name. Out on the course, he was clad in a red jacket with red matching shoes and socks. For the formalities that evening, however, the ensemble was green, as in everything - shirt, jacket, slacks, shoes and socks. In fact his luggage included 26 pairs of shoes.
Hostile weather meant that the three-ball of Sanders, O'Connor and Clontarf professional Joe Craddock, played only four holes. Which gave me the opportunity of chatting with this one-time tragic and flamboyant figure, who had a three-foot putt for the British Open at St Andrews in 1970.
The hair was greyer than when I had last seen him at Royal Dublin some years ago. He was also very much thinner than the 13st of his tournament days and there was a noticeable stiffness about his neck, as if he had had a stroke.
Sanders explained that in May of last year, he underwent surgery for torticollis, or wry-neck, one of the commonest forms of dystonia, which is a group of muscular disorders featuring abnormal posture or muscle contraction.
"I was first affected by it about four years ago and the pain was so severe that I had to quit the Senior Tour," he said. "It was like having a cramp that wouldn't go away. Then it started to get worse. I went to a top specialist in Jacksonville, Florida, who said he could stop the involuntary movement of the head but that there was only a 50-50 chance of being pain free.
"In one way I didn't want to live. Yet I didn't want to take that chance. So I went to another specialist in Canada and he operated. It took about seven hours and at one stage my heart stopped beating. I was in a coma for two days.
"Eventually when I got out of the hospital, I only weighed 135lbs (9st 9lbs) and I couldn't bathe myself for six weeks. But I'm now about 85 per cent recovered." With that, he ordered a Diet Coke.
"Can you believe it?" he smiled. "I quit drinking four years ago because of the medication I had been taking. Do you know how much I loved to party and drink champagnes and wines and all the fancy things of life? It was my life. The Sinatras, the Dean Martins, the Andy Williams and the Jack Lemmons, we were like brothers, partying all the time, you know.
"At times, I felt so down over my illness that I could have turned back to drink. I could have lost the will to go on. But I didn't. God gave me a chance to come back again. Not to lay on my little butt-butt and just feel sorry for myself."
It is an attitude that preserved his sanity after one of the greatest disasters to befall a professional golfer of his standing. Needing a par at the 18th to win the game's biggest prize, he over-hit his pitch about 25 feet past the hole, which was in its classic "Sunday" position, above the Valley of Sin.
Sanders then left his approach putt about three feet short of the target. It was a tricky one, inside the left lip. In the event, he pushed it past the right edge which meant he was tied with Jack Nicklaus, who went on to beat him 72-73 in the 18hole play-off.
Though he was prepared to joke about that three-footer to O'Connor on the first hole at Grange, he admitted in a more serious moment later on that it probably cost him $10 million per foot.
"Oh yes, it was costly," he said. "It was costly in more ways than you could ever dream. You see I had waited for that moment. I was ready. I had done all the other things - except to win a major.
"I had already been the runner-up in the PGA (behind Bob Rosburg in 1959) and in the US Open (to Gene Littler in 1961) and in the British Open (to Jack Nicklaus) at Muirfield in 1966. And I had lost the Masters by two strokes (to Nicklaus) also in 1966.
"So, by the time 1970 came around, everything was set. Had the putt gone down, I could have signed contracts that day for millions of dollars, because I had something to market. If I had won at St Andrews, Doug Sanders would always have been known as the guy who beat Jack Nicklaus in the British Open.
"But I missed it. It means I can never be in the PGA Hall of Fame, because I have never won a major. Orville Moody can be in it, though he won only one tournament (1969 US Open). You have to win a major to get into the Hall of Fame.
"I could possibly have been captain of the Ryder Cup, like Tom Kite, who won the US Open in 1992. Guys like him are remembered for the fact that they won a major. And of course that's wonderful. I'm not knocking it.
"There so many things I could have done. So yes, it hurts."
He went on: "I don't know what I would have given to be able to take that putt again. I missed it. I made the mistake when I walked up there. I made the mistake of not backing away. I made a mistake by not letting Trevino (Lee Trevino, his playing partner) putt first (before finishing out).
"I made the mistake about thinking which section of the crowd I was going to bow to. I did it all. I never blamed anybody. I never said anything. It was all my fault. There was only one person to blame. Doug Sanders.
"Yes, I would like to have that putt again. It will be there in history, long after I'm gone. They will still show that putt from the British Open of 1970. But let me tell you something. You can't go back and re-live your life. You have to look forward and move into other things."
I then reminded him of the video film on which the BBC's renowned commentator, Henry Longhurst, made the memorably sympathetic comment after Sanders's miss: "There but for the grace of God. . . ." Now, 27 years on, the player responded: "He said that? Longhurst, what a man he was."
Then Sanders went on to recount the reaction of an even greater name in golf, who happened to be watching the drama on television 4,000 miles away at his home in Fort Worth, Texas. "A friend of mine was sitting with Ben Hogan," he said. "And Hogan yelled `Back away, back away, back away.' But it was too late."
At that stage of his career, Sanders was approaching his 37th birthday and had 18 tournament victories to his credit on the USPGA Tour, starting with the 1956 Canadian Open which he won as an amateur. So, he could claim the sort of status that is enjoyed these days by Greg Norman, who gained his 18th US tour win last Sunday.
But, of course, Sanders had never won a major. And his only other "regular" tour win would be the Kemper Open in 1972. As a senior, he won the 1983 World Seniors Invitational and was runner-up to Gary Player in the 1987 US Senior Open.
"When I first came on the tour, before the game of golf grew in leaps and bounds, Arnold Palmer was king," he said. "And for me, he remains one of the greatest and one of the nicest guys you could meet.
"Then you had Player, who dressed in black. But when I came along, I dressed in all those pretty clothes and had all the pretty women following me. And I was mixing with all the Hollywood stars and I rubbing shoulders with presidents and senators. You name it.
"Along with that, I could tell some stories and do some trick shots. Sure I was marketable. Before Jack (Nicklaus) came along, we three were the ones who could sell clothing and all of that stuff. That's what made everything about 1970 at St Andrews so important."
But he has learned to live with the pain of it all. In fact he played the Old Course earlier this month while back in Scotland on a golfing holiday. How did he play the 18th? "I had a birdie," he replied with a smile. "Sank a 12-footer." Then he added: "And when I was there, I set up a pile of those three-footers - and sank them all!"
He then talked further about his contemporaries and his friendship with O'Connor, before outlining his commitment to helping young golfers, as exemplified in the Doug Sanders World Junior Golf tournament.
"Look at Christy," he said. "I've seen him in sand-traps; I've seen him in rough; I've seen him in the centre of the fairway and I've seen him hit some of the greatest shots of all. And one thing is that he doesn't change. Regardless of whatever shots he hits. If you like Christy O'Connor one day, you'll like him the next.
"I include him among the legends of my era and I believe they were different. You knew where you stood all the time. There was never anything like `I wonder if he might tee it up in the rough, or is he going to give me the right count.' They respected golf as a game of honour."
I wondered if at 64, he had managed to salvage much cash from a remarkable career. "When I became ill, I got no disability from the Tour, which was a disappointment to me," he replied.
"So I had to pay all of my own expenses. I got nothing from anybody." But surely he had accummulated some wealth from golf? "Wealth? What is wealth. Money is only chips. I can get by. I just recently got divorced. I'm back now doing exhibitions and will be returning to the Tour in the fall.
"I never put any emphasis on money. Sure I made money and I've never owed a quarter. I've got a great home. I own everything I have. All paid for. But I can't sit down and lay there for the next 100 years without doing anything - not the way I enjoy spending money.
"I got a new line of clothes coming out and I've got a new company it's called Protein International - a natural fertiliser-type company."
He concluded: "From Austin, Texas to Houston is about a 20minute flight. They said I could get on there in a 747 and before the plane landed, I would have met 90 per cent of the people on board."
That's Doug Sanders, everybody's friend, who delights in being known as the Peacock of the Fairways.