The golfing superstar is one of the world’s leading sportsmen at the moment, and he has plenty of rivals vying to take his crown around every corner.
But you might be surprised to learn that he considers Keane something of an enemy – despite being a well known and lifelong Manchester United supporter.
Keane was idolised by United fans of McIlroy’s generation after leading the Red Devils to countless trophies during his playing days at Old Trafford, but the 28-year-old Northern Irishman explained exactly where his beef stems from.
Speaking via the Telegraph, McIlroy explained why he thinks it’s important to give so much time to his followers, saying: “It just shows what such a small thing can mean to a kid. I had it go the other way for me, where I asked someone for an autograph as a kid and they didn’t give it to me. And I’ve never liked them since.
“It was Roy Keane. He should be one of my heroes because I was, and still am, a huge Man Utd fan.
“But I remember I went and asked him for his autograph at the Portmarnock Links Hotel [in Dublin] when he was with the Ireland squad and he just said no.
“And it just sort of stuck with me ever since. So that’s why if a kid asks me for an autograph, I always try to do it.”
Keane is currently with the Republic of Ireland squad, in his guise as assistant manager, preparing the squad for Friday’s crucial World Cup qualifier against Moldova.
We know one man who won’t be cheering him on – and we’re waiting with bated breath for Keano’s response!