I had some wonderful times in my 27 years caddying for Lee Trevino. We won two Opens together, at Muirfield in 1971 and Royal Birkdale in 1972, and he thought so highly of me that he wanted me to work full-time with him in America.

Yet despite all that, the occasion I most cherish is the 1967 Open at Hoylake. After trying for so long, Roberto de Vicenzo eventually won the title. And it was the most sentimental thing I've ever seen.

Though Roberto always played well in the Open, he was nearly 45 at that stage (actually he was aged 44 years and 93 days) and he felt he had missed his chance. I had been with him barely 18 months at that time, having been with Tony Lema. But we got on really well together.

If he were to succeed at Hoylake, he would be the oldest winner of the event this century. Acutely aware of this, he kept telling me that it wasn't meant to happen; that the fates were against him. And there was no boost to his confidence in the way things happened at Hoylake, even though we took the lead in the middle of the third round and never lost it.

In fact we were two shots in front of Nicklaus and three in front of Player after 54 holes. Yet Roberto, who partnered Player in the last round and was in the group ahead of Nicklaus, was made the outsider of the three by the bookmakers.

He wasn't a gambling man, but he couldn't help hearing the betting. When we were on the practice putting green, just before going to the first tee, he said to me: "Why would they do that to me? Is it because they don't want me to win?" My reply was: "Don't mind what the bookmakers think, you can win."

This wasn't enough to satisfy Roberto, emotional man that he was. "I will win if the people want me to win," he said. "But they will have to show me by their support."

The way things turned out, we did nothing brilliant for the front nine of the final round, but neither did Nicklaus. As we went to the 10th tee, I noticed the crowd were getting bigger. It was almost as if fate had taken a hand. Roberto was getting the public support he longed for. The feeling was that it was Roberto's day.

By the time we got to the 15th, the crowd was massive. Soon we were on the 16th tee and there were these chestnut fences along the fairway, nothing like the ropes we have these days. Anyway, as Roberto was on the backswing of his drive, these guys jumped back off the fence and went "Wheeee."

In the circumstances, my man did well to hit what was a reasonable drive; not a good one but okay. Anyway, this was the famous, parfive 16th with its internal out of bounds and I knew it would probably decide the championship. So I went down the fairway to figure out what Roberto should do from there. An out of bounds on the right would spoil everything.

I had no yardage. We sized up shots the proper way in those days. Anyway, after I had eyed up the shot and taken note of the wind, I had a gut feeling. So when Roberto turned to me and said "Willie, which way?", I just took the cover off the three wood and handed it to him. "Hit it," I said. "To lay up?" he asked. "No," I replied. "To hit the green."

He never hesitated. There was a carry of 230 yards into a light wind so I knew it had to be hit 100 per cent. As the ball was in flight my stomach was turning over and I prayed it would be right. Eventually, I saw it bounce on the green and I heaved a sigh of relief. Two putts and we had our birdie.

When he parred the 17th, I could see the emotion beginning to get the better of Roberto. He was heaving; trying desperately to control himself. He succeeded in hitting a fine, three wood down the 18th fairway but by the time he got to his ball, his face was covered with tears.

"Willie," he said, "I can't see the green. Give me a club that will get me there for two putts." Which I did. An eight iron. And we walked the rest of the way to the green where everybody in the stands rose to acclaim the new champion. "Viva Roberto," they kept calling. "Viva Roberto."

By that stage there wasn't a dry eye to be seen. And for Roberto and me, there would never be another moment quite like it.