UNITED KINGDOM 8 Jul, 2015 (AFP) - "After much consideration, I have decided not to play in the Open Championship at St. Andrews," the world number one said Wednesday on his Twitter and Instagram accounts.
"I'm taking a long term view of this injury and, although rehab is progressing well, I want to come back to tournament play when I feel 100% healthy and 100% competitive.
"Thank you for all your support and best wishes. I hope to be back on the course as soon as I can."
The 26-year-old Northern Irishman had revealed the extent of the injury on his Twitter and Instagram accounts on Monday.
"Total rupture of left ATFL (ankle ligament) and associated joint capsule damage in a soccer kickabout with friends on Saturday," he said.
"Continuing to assess extent of injury and treatment plan day by day. Rehab already started..... Working hard to get back as soon as I can."
He also posted a photograph on Instagram showing himself on crutches and wearing a protective boot.
McIlroy quickly pulled out of this week's Scottish Open at Gullane and it was immediately clear that the extent of the injury made it highly unlikely that he would be able to tee off in the Open championship first round next Thursday.
The Open organisers the R&A Tweeted after McIlroy had said he would be missing that they were "naturally very disappointed that Rory will be unable to defend his title at St Andrews next week.
"Rory will play in many more Open Championships and our primary concern is for his complete recovery.
"Everyone associated with The Open wishes Rory the very best as he looks to return to full fitness."
McIlroy's budding rivalry with 21-year-old American Jordan Spieth - the two of them own all four major titles between them - had been billed as the focal point of this year's Open and his absence will be sorely felt.
His misfortune was 30-year-old Scot Russell Knox's good fortune as he replaced him in the field for what will be his first Open.
"My manager received an email from the R&A to say 100% I am into the Open," said Knox, who bemoaned McIlroy's bad luck.
"I was down on the 12th hole and had a big smile on my face when I got the text. Bizarrely it was close to where I got a hole-in-one some years back."
Golfers preparing for the Scottish Open at Gullane were quick to come to his defence earlier on Wednesday.
Rickie Fowler, who is the same age as McIlroy, said that it was just an unfortunate accident.
"I haven't spoken to him yet, but it is unfortunate," the American said. "I'm of the impression that you have to live, you can't be too cautious.
"Soccer is not as big of a sport in the US, but I grew up with my fair share of action sports. That's something that I don't do as much now, but I don't stay away from completely. I still like to live and have a little bit of fun."
Fellow American Phil Mickelson, who won the Open at nearby Muirfield the year before McIlroy's triumph, concurred saying that he had undergone a similar fate in 1994.
"I snapped my finger before the Masters skiing and I said then, and I feel the same way now, you can't live your life in fear. You have to enjoy the moment," the 45-year-old said.
"I didn't feel like anything he was doing was an unnecessary risk. He was just playing around and accidents happen. People get hurt taking a shower and doing normal day-to-day things. You can't stop living your life."
It remains to be seen whether McIlroy will be fit in time to defend his PGA Championship at Whistling Straits, Wisconsin next month and even whether he will be able to play again this season.