But just like in the Postecoglou case, there was still a sense of shock when it happened.

The Cahill-in-Australia experiment didn’t make it to the 18-month mark. On the morning of his 38th birthday, he and the club both turned their keys.

It would have been marvellous if the former Everton star could have lit up the league like he did in his first season. Alas, the very riches that paid for him to come to Melbourne ended up being extended to others – principally Ross McCormack – who would compete for his spot.

Those circumstances conspired to give Cahill just 94 A-League minutes for the entire season to date. That’s effectively one single match. For the record, he played the whole 120 minutes in the second leg of the play-off against Syria. The writing was on the wall.

There will be groans of discontent (not least from anyone working in Australian football marketing) but the numbers simply don’t lie. Thirteen goals in his first season – framed by that outrageous winner on his league debut and an FFA Cup final-winning strike – made for a grand return to Australia. There has been only one goal this year.

It wasn't the relationship between club and player that went sour, for Cahill has nothing but good words about the City operation. The problem, if you can even call it that, was simply a matter of pragmatism.

Sent with a brief to win football matches and develop young talent, City’s new coach Warren Joyce was clearly not in the mood to give Cahill special treatment because of his fabled history. Nor was Joyce employed by the City Football Group to prepare Cahill for trips to Samara or Sochi.

Nobody can be critical of the Englishman for that, not even the most loyal of Socceroos’ supporters. Perhaps there was more to it but I doubt it. It just seems as simple as Cahill not being the coach’s first choice and him getting concerned about that very fact.

And Cahill, to his credit, never really whinged about the fact that he wasn’t getting enough game time. He commented that he had “some big decisions to make” but that, to me, was simply him thinking with the World Cup in mind.

I don’t view that as selfish because City knew that when they signed Cahill, going to a fourth World Cup was front and centre of his thinking.

What people may not know about Cahill is how obsessive he is about his preparation. Nobody in Australian football has put more work into eating right and training right. I’ve seen it first-hand. He’s his own personal trainer and high-performance coach, adding at least five years to his time on the field.

He also knows that he’s deep into injury time of his own career. When you get into your 30's, it becomes easier to lose fitness and harder to gain it. He’s almost 40, so is acutely aware of the odds he must defy over whatever is left of his career. Having too much down time, which is his current problem, is a high-risk strategy.

There is also the off chance that the new Socceroos coach will not be so forgiving of Cahill’s lack of match time. Especially if he’s a foreigner.

Cahill should be safely on the plane to Russia, no matter who is in charge, but a particularly strong-minded European would have no qualms about making some very tough decisions. It could be a game changer for many players, not just the nation’s all-time leading scorer.

Postecoglou always trusted Cahill, regardless of his form or club, and was duly rewarded. If Cahill stayed at City, he’d have a tough time explaining to the new boss why his form warranted a World Cup spot.

Of course, selfishly, we can be disappointed that Cahill has left because he’s a wonderfully intriguing figure on the field, not least when a set piece is being taken.

But come June, if Cahill arrives in Russia fit and ready to fire, the gain for Australia will outweigh the loss for the A-League.