Popovic was not just a head coach. That was written on his business card but his role went way beyond that.
Unofficially, he was a vice-chairman, head of planning, HR manager, financial controller and spokesperson.
No person is bigger than the club, it is said, but perhaps they can be equals.
Popovic’s authority was not challenged. The rule was simple: ‘Popa’ would make an order and that was that.
But he mostly made good calls because his vision was both well-thought out and crystal-clear.
The dictatorial approach helped drive unity, sacrifice and direction. It enabled the manager to keep his dressing room hungry and loyal.
He loved getting a talented but unfulfilled player, re-configuring their mental state, and putting them to work. His obsession with details was Bill Belichick-like.
So ruthless was the boss that certain players – especially under-performing foreigners – have never recovered. But that was the Wanderers’ way: you’re on board or you walk the plank.
Now it is Popovic walking his own plank, entirely by choice.
There’s been cries on social media that he’s abandoned ship on the brink of the season. There’s also been calls that the club messed up by allowing him an “out” clause.
Trust me, he wouldn’t have signed a new contract without it and he’s knocked back multiple offers before taking this one. He's not disloyal and the club's executive is not foolish.
At Karabukspor – five hours from Istanbul and two-and-a-half hours from Ankara – he gets a chance to fulfil the dream. It may be isolated, but it is the Turkish Super Liga; one of the toughest places to test oneself.
It’s definitely not about money. He’s has knocked back bigger offers. But he’s smart enough to know that if he does well, he can coach in Europe for the next decade, followed up by another decade in Asia.
There’s also another very realistic possibility. Popovic – who will already be under pressure just for being Australian – won’t be given long to get it right.
If it doesn’t work out, he could be a free agent by the time Ange Postecoglou leaves the national team post next June. Just keep that in mind.
Either way, after becoming the first Australian coach to win the Asian Champions League, he becomes the first Australian to coach at the highest level in Europe, which means he’ll never be short of a job.
It’s a win-win, all while giving his assistant coaches Zeljko Kalac and Andreas Carrrasco a priceless leg up in their careers, too.
But the real question is about the Wanderers as a whole.
The umbilical cord has been cut. Now they have to go it alone. But managed correctly, it’s an opportunity to shape how the club ought to be run for the next decade.
So far, the club has operated without a technical director. Given their burgeoning youth academy, and aspirations to create something exceptional in western Sydney, it makes sense to find somebody capable of overseeing the club’s long-term aspirations.
Popovic effectively filled that role himself – but the club is big enough now to find somebody qualified for that role.
As for the coach, elite domestic options are thin.
Mark Rudan has been waiting years to be called up to the big time. A close confidant of Tony Popovic, he’s a good option if the club wants to maintain consistency. As a long-time coach of Sydney United, he also knows the western Sydney market intimately.
Socceroos’ assistant coaches Josep Gombau and Ante Milicic are possibilities but have commitments with the national team that could be over within a week or go on for eight months.
David Zdrilic is a rising star of the coaching fraternity but having been poached from Sydney FC to join the revolutionary setup at RB Leipzig, he won’t be coming home soon.
Brisbane Roar’s championship-winning coach Mike Mulvey is oft-mentioned but he's contracted to Thai league club BEC Tero Sasana.
Both Aurelio and Tony Vidmar are free agents. Could they perform the league’s second all-brother double act?
There’s countless brilliant coaches currently without jobs in Europe and South America, although whether the club has the resources and networks available is another question.
Whatever the decision, it’s a hell of a job to replace Popovic.
He carved the club in his image, but now it’s time for the club to carve out an image of its own.