IF you are reading this over an early morning breakfast then there is a chance that he will still be playing in the Australian Open.

If you are reading this over lunch, the chances are that the playing career of the greatest Scottish sportsman of all time will be over.

If you are reading this at tea-time, I expect you’ll be like so many people around the world and will have been deeply affected by something as gloriously trivial as a tennis match. For once, though, sport is not trivial, not when the fate of a genuine hero is at stake.

As I write this on Sunday afternoon, Andy Murray is one sleep away from the match which will decide his immediate fate. At his peak, the man from Dunblane would be hot favourite to beat the Spanish 22nd seed Roberto Bautista Agut when they contest their first-round match in the Australian Open in Melbourne.

The match is scheduled to start at around 7am, and I for one am setting the alarm to watch it on Eurosport.

Bautista Agut will be a very difficult opponent, not least because he beat world No 1 Novak Djokovic on his way to winning the Qatar Open last week.

I was struck by what Agut said about Murray at the weekend – that he still expects a tough match, despite knowing Murray is feeling pain when he plays and could quit if he loses.

Agut said: “Everybody knows when Andy goes on court he gives 100%. He has fought all his career and Monday’s match will be the same.”

How so very true, and how so very tragic. For, like us all, Andy Murray is ravaged by time more than anything. The sheer duration of his career in the very top ranks of tennis has been his undoing, because no-one who plays such a physical sport with his intensity can walk away unscathed.

He wants to limp on to Wimbledon, but limp might be the operative word.

The sheer effort of his approach to tennis has taken its inevitable toll on his hip with his surgeon Dr John O’Donnell saying yesterday: “He enjoys the Australian Open, and has been very keen to play, but Wimbledon is the high point for him.

“Ideally he would want to play there, but I imagine once you make the decision that you are going to stop it must get very difficult to keep going with the rehab, never-ending exercising, and putting up with the pain.

“Once you see the end in sight, I guess it would be harder to get motivated.”

Dr O’Donnell added: “Andy has tried really hard and explored every option that has any real possibility of being helpful. Realistically I don’t think there is anywhere else to go to preserve his hip and get it better so he can continue to play. That won’t happen now.”

The verdict is in – the question now is only this: when?

I wish I did not have to write this, but as someone who has followed every twist and turn, every up and down in his extraordinary career since he was a schoolboy, I think Murray should call it a day today, even if he wins, and not put himself through that pain barrier once again.

It may be that, with the help of a massage and some painkillers, he will make it to Melbourne Park. Maybe by some miracle he might even win, but the likelihood must be after the scenes of last week that this will be his last match as a player and that Agut will go into the second round.

Yet you never know with the Scotsman who has fought from behind on so many occasions. He has put us through the emotional wringer on more occasions than I care to remember, and I would not put it past him to conjure up something miraculous today.

The inevitable is only being kicked down the road, however, and much though I would like Murray to go out on a high at Wimbledon, I can’t really bear the idea of him playing on through the pain. It’s tough enough even to watch, so how much worse is it for him?

He should think of his wife Kim and his young children. Aye, and his mum and brother and his extended family and all of us who see him as a legend of our time.

Andy Murray proved how brave a personality he was back in September, 2014, when he tweeted his support for Yes. This was what he said: “Huge day for Scotland today! No campaign negativity last few days totally swayed my view on it. Excited to see the outcome. Let’s do this!”

(I always thought his remark about the “No campaign negativity” was perspicacious and accurate. It was a lesson for the Yes movement, one we should learn. Keep it positive!) No-one doubts Andy Murray’s courage, ever. But sometimes the brave thing to do is to walk away. That time has come for our Scottish hero.