Tiger Woods was among the first players to post congratulations to his friend.
“Welcome to the club @McIlroyRory. Completing the Grand Slam at Augusta is something special. Your determination during this round, and this entire journey has shown through, and now you’re a part of history. Proud of you,” the 15-time major champion, who completed his Grand Slam in 2000, wrote on X.
Jack Nicklaus, winner of a record 18 majors and six Masters titles was the fourth man to complete the Slam, in 1966.
The 85-year-old said on America’s CBS: “I’m so happy for him. It will take the world off his shoulders and you’re now going to see a lot more of really good golf out of Rory McIlroy.”
And Gary Player, at 89 the oldest living member of the now six-strong Grand Slam club, wrote on X: “We are proud to add Rory to our exclusive club and no doubt he has set the standard for his era.
“It was 11 years ago when Rory first started the final leg of his career Grand Slam journey. And throughout this time, he’s carried himself with class, led with principle, and played with passion. For him to finally don the Green Jacket is a moment to be celebrated by fans around the world.”
Meanwhile Ryder Cup team-mate Shane Lowry, who faded out of contention on Sunday with an 81, told BBC NI Sport: “It’s huge for Irish golf. It’s huge for everyone. I’ve had a really bad day but I’m delighted for him.
“He might not have wanted to say this but it’s genuinely been everything for him over the past 10 years.”
And on X, Ireland’s 2019 Open champion wrote: “He always said to me he’d retire a happy man if he won the Green Jacket.”
England’s Tommy Fleetwood said it was “a very Rory McIlroy way of doing it” and nobody could “have written a better script”, adding: “I couldn’t be happier for him. He’s at the top of his game and he’s achieved something incredible.”