Rory McIlroy is finally living the dream he’s chased for over a decade. With his long-awaited victory at the 2025 Masters, the Northern Irish golfer has officially completed the career Grand Slam — a feat that had eluded him for 11 years. It was an emotional moment, marking his fifth major title and the end of a drought that had fans wondering if it would ever happen.

“I could be sitting up here with a fifth Major title and I am not. So that stings and that’s something I have to come to terms with but … I’ve got plenty more opportunities in the future,” McIlroy had said back in November 2024. And when the opportunity finally came this April, he aced it.

But as much as the spotlight was on McIlroy, there was also someone who quietly stood at the center of it all — his caddie, his confidant, and more importantly, his best friend. So, who is this man behind the bag?

Who is Harry Diamond?

If you saw McIlroy break down after sinking the winning putt, the first person he hugged was Harry Diamond. Diamond isn’t just someone who carries McIlroy’s clubs. He’s been by his side as a friend since their childhood days in Hollywood, Northern Ireland. The two literally grew up together, played junior golf at Holywood Golf Club, and have shared countless memories — on and off the course.

Diamond was a pretty solid golfer himself, once holding a +2.5 handicap and even representing Ireland at various amateur events. In fact, he won the West of Ireland Championship in 2012, which earned him a start at that year’s Irish Open. But he didn’t turn pro. Instead, he got involved in his family’s property business in Belfast and eventually dabbled in hospitality, owning a few bars. Still, golf never left his heart.

So when McIlroy parted ways with longtime caddie JP Fitzgerald in 2017, the decision to bring Diamond on board felt natural. Their first tournament together? The WGC Bridgestone Invitational in Ohio. And since then, it’s been quite the ride — 26 professional wins, 14 PGA Tour victories, two FedExCup titles, and now, the one that completes the Grand Slam.

What’s in the bag for Harry Diamond?

Caddying for someone like Rory McIlroy isn’t just a passion project — it pays well, too. Caddies typically earn 10% of their player’s winnings, so with McIlroy’s $4.2 million Masters prize, Diamond likely took home around $420,000 just from that week. Add to that a reported weekly salary of $3,000–$4,000 and other season wins, and Harry’s estimated 2025 earnings so far fall somewhere between $870,000 and $900,000. Not bad for someone who prefers to keep a low profile, right?

And he really does keep it low-key — no social media, no tell-all interviews, just doing the job with quiet confidence.

But more than the paychecks, it’s the bond he shares with the World No. 2 that means the most to him.

Harry Diamond and Rory McIlroy share a strong bond

What truly sets this duo apart, though, is the depth of their relationship. They’re not just golfer and caddie — they’re best friends. So close, in fact, that Harry was McIlroy’s best man when he married Erica Stoll in 2017.

Their bond reflects in their chemistry on the course. As McIlroy once said, “I was an only child and Harry was a big brother. We’re very close. I love having him on the bag. I’m a different person. And I’m never going to give him sh** even if something goes wrong. It would not be worth it.” That kind of trust and mutual respect can’t be taught — it’s built over years. And it shows. Diamond isn’t the loudest voice on the course, but he’s exactly what McIlroy needs.

Of course, no relationship — especially one so public — goes without its share of criticism. After McIlroy’s heartbreaking finish at the 2024 U.S. Open, some questioned Diamond’s club selections. But McIlroy didn’t hesitate to defend him, even calling out critics like Hank Haney and Smylie Kaufman by name.

“Just because Harry is not as vocal or loud with his words as other caddies, it doesn’t mean that he doesn’t say anything and that he doesn’t do anything,” McIlroy clapped back. “These guys never say anything good when things go my way, but they’re always there to criticize when we don’t win.”

That loyalty goes both ways. Even when Diamond briefly stepped away in 2022 for the birth of his second child and Niall O’Connor filled in, McIlroy was quick to welcome him back. And back he came, as devoted and dependable as ever.

Diamond once swapped studying yardage books for planning McIlroy’s stag party in Miami. Now, he’s by his side at Augusta, helping him make history. That journey, that bond — it’s what makes their story one of the most heartwarming partnerships in the sport.

They say golf is a lonely game. But Rory McIlroy proves that with the right person beside you, even the loneliest battles become something unforgettable.