Rory McIlroy's Open defence all but over after rupturing ankle ligaments

          Ross Kinnaird/Getty Images
          • ESPN staffJul 6, 2015, 06:11 AM ET

          Rory McIlroy's Open Championship defence is in tatters after he ruptured ankle ligaments playing football with friends.

          McIlroy posted a picture of himself on Instagram wearing an Aircast on his left leg.

          "Total rupture of left ATFL (ankle ligament) and associated joint capsule damage in a soccer kickabout with friends on Saturday," he wrote.

          "Continuing to asses extent of injury and treatment plan day by day. Rehab already started..... Working hard to get back as soon as I can."

          The world No.1 is likely to be out for several months, meaning his chances of defending the U.S. PGA Championship at Whistling Straits in August are also in doubt.

          His spokeman, Sean O'Flaherty, said he was definitely out of the Scottish Open, which starts Thursday at Gullane. O'Flaherty said they would not know until the end of the week the prospects of McIlroy teeing it up at the Open Championship, which begins at St. Andrews on July 16.

          McIlroy has won four major championships to date, including last year's Open at Royal Liverpool.

          He will have further scans over the next 48 hours, but if examples of Premier League footballers suffering the same injury in recent years are anything to go by, then he is likely to be out of action for at least four months. The left ankle is crucial in a golf swing as weight shifts to that side while generating power.

          If, as expected, McIlroy misses the Open, it will be the first time he has missed a major since the U.S. PGA Championship in 2008.

          McIlroy was the joint favourite at St Andrews with Jordan Spieth, the 21-year-old Texan who has won the Masters and U.S. Open and goes to the Open Championship as only the fourth player with a shot at the modern Grand Slam.

          McIlroy won the Open last year at Royal Liverpool by going wire-to-wire and taking a six-shot lead into the final round. He also won the PGA Championship, joining Jack Nicklaus, Tiger Woods and Bobby Jones as the only players in the last century with four majors at age 25 or younger.

          "That's a big blow to the Open if he misses it," former Ryder Cup captain Sam Torrance said from Wimbledon, while Sir Nick Faldo took to Twitter to express his disappointment.