There could not have been a starker contrast to the conclusion of the second-round matches of Rafa Nadal and Andy Murray at the Australian Open last week.

While Murray heroically battled back to defeat Thanasi Kokkinakis over five sets and in nearly six hours, Nadal’s straight-sets defeat to American Mackenzie McDonald was the Spaniard’s earliest exit at Melbourne Park since a first-round loss in 2016, and felt far more significant than just a blemish on his Grand Slam record.

It was not only the loss so early in the tournament that was dispiriting, it was the manner of it. To see him limping off court, accompanied by a poignant and forlorn wave, left you wondering where the Spaniard goes from here.

The feeling is that retirement is, if not imminent, then looming for Nadal.

The hip injury he suffered during his loss to McDonald will need six to eight weeks to heal and for someone who’s had consistent injury issues throughout his career, it’s a blow he did not need.

Nadal’s woes are as bad as he has ever faced. He’s lost seven of his past nine singles matches, a stat that would be unimaginable at his peak.

And his injuries are now becoming almost incessant. For an athlete who relies so heavily on his physicality, there is, unfortunately, only going to be one winner in this war.

Nadal has made no decision and if he is physically capable, he wants to continue playing.

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But as someone who is so used to being a consistent contender for every major tournament he enters, the appeal of continuing if he is not at least competing for, never mind winning titles, will quickly wane.

His departure from tennis will be a monumental blow to the sport. Of all the staggering statistics that the big four of Nadal, Roger Federer, Novak Djokovic and Murray have accumulated, perhaps the most spectacular, and most under-rated and under-reported, is that Nadal has occupied a place in the world’s top 10 in the world for almost 18 years straight.

Since he broke into the top 10 in the world in April 2005, he has never been out of it. That is over 6,000 consecutive days.

Nadal is perhaps the greatest competitor sport – and I mean any sport – has seen.

Athletes are always talking about taking things one point at a time but Nadal is the only one who seems truly able to do that.

His mental strength is unmatched and so to see his body fail him, in the past six months in particular, is hard.

Certainly, Nadal shouldn’t be written off entirely, however down and out he seems.

This time last year, another Grand Slam title seemed a ridiculous prospect for the Spaniard, but just a fortnight later, he won his first Australian Open title for 13 years, and just a few months later, won a record 14th French Open crown.

His own recovery skills are remarkable, and the comeback of Murray reminds us that you dismiss these exceptional athletes at your peril.

Nadal may prove the doubters wrong, at least for a short time. I hope so, because there’s unlikely to be another like him.

AND ANOTHER THING

Once again, the farce that is athletes switching nationality on a whim raises its head.

Gregor Townsend’s inclusion of Ruaridh McConnochie in his Six Nations squad means London-born McConnochie is on the verge of becoming the first rugby union player in the modern era to represent both Scotland and England.

With three years having passed since his last England cap – at the 2019 World Cup – the recent rule changes on eligibility mean the 31-year-old, who has a Scottish father and spent much of his childhood in Scotland, can switch nationality.

“People disagree about the ruling but I think ‘why not’?” said McConnochie, after being named in Scotland’s Six Nations squad last week.

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It’s hardly a rousing declaration of his love for Scotland, is it?

The entire meaning of international sport is based on feelings of pride and love for your nation but it’s becoming increasingly clear that more often than not, athletes’ primary motivation to switch nationality is to further their often stalling

careers rather than through any sense of attachment to their new nation.

Admittedly, there has to be some leeway for athletes to change nationality during the course of their career but it’s gone too far.

Much stricter boundaries must be imposed or international sport, particularly sports like rugby union which is making it increasingly easy and seamless to switch, is in danger of losing all that is great about it.

We have already got club sport, we don’t need more of it by turning international sport into an extension of the club game.

Time will tell if McConnochie does indeed win his first Scotland cap at these Six Nations but with every nationality switch of a player, for me at least, the love of international sport diminishes.