JP Fitzgerald first took notice of his future employer during the 2007 Open Championship at Carnoustie, where Pádraig Harrington made his Major breakthrough. Rory McIlroy was in pursuit of the amateur medal and Fitzgerald was working for Ernie Els.
"On television, I saw Rory hit a two-iron second shot into the wind to the last," the caddie recalled. "What really impressed me was that with 230 yards to go, he hit it so high up in the air that it stopped on the green almost where it landed. I later made a point of saying to him: 'That was a special shot'."
Before the end of the following year, Fitzgerald had become McIlroy's caddie. And they've been together since then, sharing seven tournament victories, including the 2011 US Open and last Sunday's PGA Championship.
During that period, the relationship has come under severe pressure, but only from outside sources. For instance, Fitzgerald was widely criticised for failing to lift his man during a dramatic back-nine collapse in last year's US Masters. And during the Irish Open three months later, he became a central figure in a very public spat involving McIlroy and TV pundit Jay Townsend.
While the two professionals were Tweeting bitter words to each other, Fitzgerald maintained a dignified silence. Having been highly critical on RTE and America's Golf Channel of the course-management of player and caddie at Killarney, Townsend then repeated it on Twitter, using such terms as "shocking" and "some of the worst (course-management) I have ever seen beyond under 10s boys golf competition."
By way of reply, McIlroy Tweeted: "Shut up . . . you're a commentator and a failed golfer, your opinion means nothing." Townsend then insisted he stood by his comments, to which McIlroy replied: "Well I stand by my caddie."
As it happens, I can claim a role, albeit extremely small, in JP's development into a leading tour caddie. It began at the 1994 World Cup at Dorado Beach, Puerto Rico, where he had no place to stay when he arrived to caddie as a friend for Paul McGinley. Given that I had quite a spacious hotel room to myself, he became my guest for the week.
From there, he proceeded to embark on full-time caddying for McGinley, with whom he stayed until Christmas 2002. Then he joined another Irishman, Darren Clarke, early the following year and was with him when he captured top prize of $1.05m in the 2003 NEC Invitational at Firestone. And from his 10 per cent share of those winnings, Fitzgerald bought his mother a Mercedes car.
His next big bag was with Ernie Els, before he teamed up with McIlroy. Meanwhile, he gained the distinction
last July of being able to
claim a matchplay victory over an Open champion. This dated back to the 1987 Irish Close at Tramore where he beat Clarke on the 20th in the semi-finals, only to lose the final to Eddie Power. He also had a competitive match against McGinley, but with a rather different result.
Their duel was in 1991, when Co Louth met Grange in the Leinster final of the Irish Senior Cup. "It became quite a story," recalled McGinley. "I happened to play JP, who I had known from the time we were juniors. Later, when I was away at college in San Diego, he would come out and visit me."
Friendship was forgotten, however, when Fitzgerald began teasing as to how he planned to do to McGinley what he had done to Clarke four years previously. Which made the Grange player all the more determined to produce of his best. "In the end, I hammered him 5 and 4 and even now, 21 years on, it remains an important match," he said. "I must admit I found it funny when he'd have a go at Darren over the Tramore episode, but when he dares have a go at me, I promptly throw that Senior Cup result at him."
Perhaps fortunately for their current relationship, a considerable age-gap meant he and McIlroy never crossed competitive paths. "JP has become a really good friend of mine," said the newly-crowned PGA champion. "He's been very loyal to me and I feel I've been very loyal to him. I like being able to talk to him in between shots about things other than golf on the golf course. Takes my mind off it."
They certainly seemed to work wonderfully together at Kiawah Island. When Fitzgerald talked of the way Ian Poulter was closing in on them last Sunday, I asked him if he had brought this to McIlroy's attention.
"You don't have to bring those sort of things to this fellow's attention," he replied. "Rory knows everything that's going on. Believe me. You might say he's a bit of an anorak."
He went on: "I wouldn't compare this with Congressional (US Open). On the range that Sunday morning in Washington, I thought he could win by 12 shots. But this one was different -- a very special performance that he really had to fight for. And the way he responded . . . I knew it was all over when he birdied the 12th."
They now rival Harrington and Ronan Flood as an Irish working partnership at this level. Which makes their latest success all the more appealing.