Further scans in the coming days will likely determine if Rory McIlroy, the world number one, will be sufficiently fit to defend his British Open title at St Andrews next week, although a full rehabilitation programme has already begun on his damaged left ankle.

The golfer suffered a rupture to his ATFL ligament when playing football on an astroturf surface with friends at home in Northern Ireland on Saturday, an injury that typically carries a recovery timescale of 10 days for a minor strain and six to 10 weeks for a more serious injury.

McIlroy, who revealed the injury in a post on social media, and missed out on a planned trip with his Ryder Cup teammates to Wimbledon yesterday, sustained the injury in what seemed an innocuous ankle twist as he ran towards the ball in a friendly kickabout. He has withdrawn from this week’s Scottish Open at Gullane, and where and when he will play in the immediate future is unclear.

In his post on social media sites, McIlroy said: “Continuing to assess extent of injury and treatment day by day. Rehab already started . . . Working hard to get back as soon as I can.”

Further treatment

A decision on his possible participation in defence of the Claret Jug over the Old Course will, according to his manager Seán O’Flaherty, only become clearer later in the week after further medical treatment, observation and examination, although a number of medical experts in the field of sports science believe it could yet prove possible for him to compete in the Major.

In old fashioned parlance, what McIlroy has suffered is an ankle sprain. It is the severity of the sprain, however, that will determine if he can defend his British Open title next week.

Pictured on Instagram wearing a boot to alleviate weight-bearing, McIlroy is on a treatment programme that is likely to entail extensive icing – every two hours – as well as physio on his soft tissue and electrical muscle stimulation. If he is to have any likelihood of defending his title, McIlroy would be expected to be able to walk nine holes, with the aid of strapping, by Tuesday.

With no timeframe for his return, it really is a case of assessing him day-by-day in the hope that he will be able to tee up in the Open at St Andrews, one of his favourite courses. McIlroy is also due to defend his WGC-Bridgestone Invitational and US PGA Championship titles inside the next month.

Dr Conor O’Brien, a consultant clinical neurophysiologist at the Sports Surgery Clinic in Santry, and a former doctor to the Irish Olympic team, said: “I haven’t examined him . . . but when you damage one of the three lateral ligaments in your ankle, and the most common one is the ATFL, which is the one they have reported on, it averages about six to eight weeks [recovery] . But when it is complicated and you damage a capsule or injure a bone, or a nerve, it can take a number of months . . . unfortunately, it is [potentially] a significant injury.”

‘Twist too far’

Speaking to the Golf Channel in the US, Dr James Gladstone, a co-director of sports medicine at Mount Sinai and medical advisor to the US Davis Cup team, explained, in general, the nature of McIlroy's injury: "The ankle can be considered a hinge joint, most of its movement up and down, but it does twist side to side as well; the ligaments which are on either side of the ankle control that side-to-side twisting, so if you twist too far you are going to hurt the ligament. The ATFL is the most commonly injured, to the front off to the outer side . . . if that's the only one torn in isolation, it's definitely the easier one to recover from."

The exact nature and extent of McIlroy’s injury will reveal itself in the coming days.

One factor in McIlroy’s favour could possibly be the fact that St Andrews is a relatively flat course, and it is also a links that he knows intimately. Although not ideal if unable to play his customary number of practice rounds, he at least knows his way around the Old Course.

Other players have managed to play with similar injuries. Davis Love III, in the past, competed with ATFL strain before undergoing surgery.

And, of course, Tiger Woods competed in – and won – a 19-hole play-off against Rocco Mediate in the 2008 US Open at Torrey Pines with a torn ACL and a double stress fracture in his left knee.

What’s for sure is that McIlroy is in the best medical hands.