There’s a few different notes on which to retire.

There’s the perfect way; for an athlete to go out on their own terms, at a time of their choosing, when they feel like they’ve achieved everything they want to in their chosen sport.

Then there’s the ones who retire because they’re just not good enough anymore. They might still be able to compete, but as winning becomes less and less frequent, they decide it’s time to call it a day.

And then there’s the nightmare scenario; being forced to retire through injury.

This is, there’s no question, the very worst of all worlds for any elite athlete.

At the best of times, sporting careers are short but when they’re cut even shorter, it can feel catastrophic for the athlete involved.

It’s this third scenario that Andy Murray is currently being faced with.

During his third-round loss in Miami to Tomas Machac earlier this week, Murray hurt his ankle, an injury that’s turned out to be more serious than most onlookers first thought.

“Towards the end of my match in Miami I suffered a full rupture of my ATFL and near full thickness rupture of my CFL,” he wrote on social media.

“Goes without saying this is a tough one to take and I’ll be out for an extended period,” he continued before insisting he’ll be back in action when he regains fitness.

So, despite what must be a hugely demoralising setback – reports have suggested he could be out for up to a year – Murray clearly feels he has the drive and commitment to go through the weeks upon weeks of rehab work that’ll be required for him to return to full fitness.

We shouldn’t be surprised.

The Herald: Andy Murray

Over the past few years, it's become increasingly apparent that Murray has been reluctant to even contemplate retirement.

A serious injury in 2019, which resulted in a metal hip, would have been a sign for most people that it was time to call it a day. But not Murray.

The former Wimbledon champion has battled ridiculously hard to return from that potentially career-ending injury and, until recently, refused to countenance any talk of retirement.

Last month, he finally caved to the incessant questioning about when his career will end, revealing he was “unlikely to play past this summer” but that information was only given after he admitted he was sick of being constantly asked when he was going to call it quits.

It’s clear, then, that retirement is not a prospect Murray particularly relishes.

Few athletes do.

Overnight, retirement means the loss of routine, loss of structure and, in so many cases, the loss of purpose in one’s life.

Add to that, in Murray’s case, he’ll immediately lose the adrenaline rush that comes with stepping out into an arena to do battle, metaphorically, with another man with tens of thousands of people watching on.

Nothing replaces that feeling, ever.

But despite the certain losses that come with retirement, if it happens on an athlete's own terms, it’s just about bearable.

Roger Federer, not surprisingly, has led the way in terms of farewells.

The 20-time grand slam champion’s results had been flailing for several years before he finally hung up his racquet for good but his final swansong was as close to a fairytale as any athlete can get.

In the Laver Cup, an exhibition team event between Europe and the rest of the world that Federer himself had founded, the Swiss former world number one played doubles alongside his greatest of rivals, Rafa Nadal, before a video montage jammed packed full of people extolling his greatness was played to the crowd while Federer and Nadal held hands and watched on in tears.

Even the greatest script-writer couldn’t have penned a more perfect send-off.

But for every heartwarming tale of retirement like Federer’s, there’s dozens, nay hundreds, that are on the other end of the spectrum.

Murray, while a distinctly different personality type from Federer, was surely aiming for something closer to the Swiss’ valediction than the hundreds of others who limp away from their sport after being struck down by injury.

The real challenge of retiring due to injury is the almost complete absence of closure.

Retirement from elite sport is tricky at the best of times.

There’s few other careers which end with, as in most cases, the individual well under the age of 40 staring at the gaping abyss now in their lives.

And it’s an abyss that’s unlikely to ever be fully filled by anything else in the remainder of their life.

It’s still a loss walking away from your career, but it’s eminently more bearable doing it on your own terms.

What’s so much more difficult to cope with is having your career snatched away.

This is what Murray’s now facing.

Ironically, this month has seen him produce some of his best post-metal hip form; after his impressive first round win over former world number six Matteo Berrettini in Miami, Murray wrote “life in the old dog yet” on the camera lens in a clear dig at those who say he should call time on his career.

He then, to prove his point, beat world number 30, Tomas Etcheverry, before suffering his ankle injury in the next round.

It’s these glimpses of form that would make it just so cruel if he is not able to return to the court in anger ever again.

Every good performance convinces Murray that he still has it in him to challenge the world’s best.

If he’s forced to retire with that fire still burning within him, it will make the process of retirement so much harder than it would otherwise be.

This doesn’t mean Murray won’t be able to deal with the ramifications of retirement - there’s few people with four young kids as he has who would find it hard to fill their days – but coming to terms with the loss of his career, especially if it comes prematurely, will likely be challenging.

Murray’s proven that he’s someone who can overcome seemingly insurmountable odds – but being forced to retire due to injury might just be the toughest challenge he’s faced to date.