Rory McIlroy admits when he last paid a green fee after awkward PGA Championship moment

is a Grand Slam champion, has made more than £75million in career prize money, and is one of the most recognisable sports stars on the planet. However, it seems he at least hasn't forgotten what it was like to be an amateur.

The 36-year-old is currently struggling at the after only scraping inside the cut line on Friday. He finished one-over-par after 36 holes, the exact score needed to be inside the top-70 and return for the weekend. His wheel at Quail Hollow has not been without controversy, though, with the star .

He's also left the course after both his rounds without speaking with the media. However, before the tournament got underway, he cut a more relaxed figure, especially when made to recall one particular golf memory by a journalist.

"When was the last time you paid a greens fee?" he was asked, following one of his practice rounds. "Where was it, and how much (did you pay)?"

The world No.2 was anything but flummoxed by the enquiry, though. Quick as a flash, he smiled as he responded: "Valderamma in 2005. It was 250 euros."

That year, the star turned 16. Just two years later, he turned professional, going on to record 44 tournament wins, including five major titles.

The @golfdigest Instagram account made light of the exchange, posting a graphic of McIlroy laughing at the question. They captioned it: "A reminder that it's been two decades since Rory paid for a greens fee," complete with a laughter emoji.

The Masters champion has become renowned for being generous with his income. He has a history of supporting Mencap through his Rory Foundation, including the building of a children's centre in Belfast.