Rory McIlroy's struggle to win his fifth major championship is well-known.
The Northern Irishman entered 2024 knowing if he is unsuccessful at this years Masters, Open, U.S. Open and PGA Championship he can expect a flurry of headlines relating to how it will be a decade since his triumph at Valhalla in near darkness.
Over the years golf fans, pundits and former players have offered their theories on what has gone wrong for the Northern Irishman.
Cliches have appeared in abundance. He has been accused of not having the bottle. Others have suggested he has lost the X factor of his youth.
To some, the problem appears to be with a putter that refuses to behave at crucial times.
- McIlroy removes himself from PGA Tour group chat after hearing Spieth's comments
- Picture of Rory McIlroy's caddie prompts unanimous reaction from golf fans
Or maybe the fact he's too cautious in round one, leaving himself with far too much to do over the weekend.
Diamond, a school friend of McIlroy's and talented golfer in his own right, replaced JP Fitzgerald in 2017.
Fitzgerald was on the bag for all four of McIlroy's major victories and the duo worked together for nine years.
"It was partly to do with him and mostly to do with me," McIlroy previously said of their famous split.
"I wasn't playing the best and was frustrated at myself and taking it out on him."
PGA Tour pro Michael Kim offered his verdict on this topic in a recent Q&A on X.
Kim, if you didn't know, has amassed quite a social media following over the last two years.
One golf fan asked Kim if he believes McIlroy should hire a professional caddie to perhaps change his fortunes.
"No doubt in my mind he gets over [the line] at '22 Open with say, a John Wood," the user wrote.
McIlroy was beaten down the stretch by Cameron Smith at the landmark, 150th Open at St. Andrews in 2022.
The defeat left an inconsolable McIlroy in tears on the back of a golf cart alongside his wife Erica Stoll.
Kim replied: "That's like one variable among 10k. Didn't he lose the Masters against Cabrera when he had JP on the bag as well?
"I could have caddied for Rory and he would have won four majors at that point in his career."
McIlroy is, of course, highly unlikely to change his caddie anytime soon.
As you would expect, he is a fierce defender of Diamond whenever their relationship as player-caddie is called in to question.
He has labelled Diamond an 'easy target' in the past.
"I think over the years I've proven I know what I'm doing out here," he previously said.
"I wouldn't have him on the bag if I didn't think he was good at what he did.
"Harry's a really calming presence to have by my side."
McIlroy has won the FedEx Cup twice with Diamond on the bag and multiple titles on the PGA, DP World Tour.
- Jordan Spieth provides blunt response to reporter over future PGA Tour-LIV deal
- Revealed: When and where Tiger Woods will unveil 'next chapter' after Nike split
- Rickie Fowler: There has to be punishments for returning LIV Golf players
- PGA Tour pro defends 'BS' Pebble Beach sponsor exemption: "I get it looks bad"