This week’s Memorial will be McIlroy’s last event before this month’s US Open at Shinnecock Hills – and he revealed he undertook a scouting mission to the New York course earlier this week.

McIlroy missed the cut when Shinnecock last hosted the US Open in 2018, and while he was buoyed by what he saw before this year’s championship, he outlined the importance of tournament organisers the United States Golf Association (USGA) maintaining control of the green speeds.

In 2018, Phil Mickelson apologised for putting a moving ball on Shinnecock’s sun-baked greens, while in 2004 the par-three seventh green was called “unplayable” and had to be watered during the last round after two players putted off the green into bunkers.

“The fairways are very generous. They’re more generous than they were in 2018 but the first cut of rough is five inches long,” said McIlroy.

“The greens are rolling around 11, 11.2 [anything over 12 is considered fast and last year’s US Open at Oakmont was between 13 and 14], something like that and I really don’t think they need to get much faster.

“I think if they can keep them at that speed they can get them firm and use the hole locations that they want to use without having some of the struggles that they have had the last couple of US Opens.

“It’s all about them just maintaining the green speeds really where they are, not getting them too out of hand, and I think it will be a great week.”

Grouped with two-time major winner Justin Thomas, McIlroy begins his bid for a first Memorial win at 15:25 BST on Thursday.