“I AM underwhelmed. We’ve appointed a 55-year-old from Australia. Is that the sort of appointment ambitious, big clubs make?”

Those were my initial thoughts the day Ange Postecoglou was announced as Celtic manager. There we were - two weeks after the collapse of the Eddie Howe deal and seemingly from out of nowhere Postecoglou in a shumper, shadowed by Dom McKay (remember him?), arrives in Glasgow ready to usher in a new era. I wasn’t quite Alan Brazil levels of indignant about it but I was curious about where the club was headed with these two newbies.

Fast forward some nine months and I can only say: I was wrong. And that’s fine! I know nowadays to some 'being wrong' about a football opinion is a crime punishable by death in the court of social media but, to me, opinions are allowed to change.

There’s no way, in those first days after Postecoglou's arrival with the disaster of the previous season and the judgement shown by those who run the club, that anyone would think in less than a year Celtic would be on the precipice of a ‘winner-takes-all’ match against Rangers for the league.

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That’s what this game is, by the way: winner-takes-all. Celtic have battled their way to the top of the table with an astonishing run of form and consistency since the start of the year - turning over a points deficit that had some people calling the league in October to be in a position where, if they beat Rangers at Ibrox, the job is done.

And it’s all down to Postecoglou. He is exactly the right man for Celtic at exactly the right time.

After last season, the club needed a manager with an old-school work ethic. A manager with soul and passion for the game. A manager whose team played with a Celtic identity, who knew what this club was and where it needed to be as well as the standards needed to get there.

Postecoglou is a manager in the mould of Jock Stein, Billy McNeill and Martin O’Neill – in his work ethic, in the way he carries himself and in the way he represents the club. The only thing missing is success. And that will come on Sunday when Celtic wrap up the league at Ibrox.

Postecoglou doesn’t need to win at Ibrox, or even win the league to prove the doubters (me) wrong. He’s done that already. He’s made lots of people (me) look very stupid simply by doing what he’s always done at every club and in every job. He’s reminded us (me) to keep the faith. More importantly, he’s given us our club back.

I’ve never been surer of anything. I’m obsessed with this team. I've gone from indifference to intoxication - and yes I’m talking Alan Brazil levels this time.