"Don't be a manager, for God's sake," Postecoglou declared with a smile when asked what his message would be to those youngsters back home who looked up to him and wanted to be where he is now.
But that response to an Aussie TV reporter at his official unveiling as Nottingham Forest head coach was actually just the prelude to Postecoglou explaining eloquently why he hopes his rise from a faraway land to the centre of the football universe can resonate with the next bunch of soccer dreamers back home.
"It's not something very easy for me to verbalise, but I think for anyone who does come from Australia, we realise just how far away we are from this world," explained the 60-year-old on Thursday.
"I think even to this day, people, particularly here in the Premier League, think I only started coaching two years ago when I took over Spurs. It just seems everything I'd done up to that point doesn't really resonate with anyone, but that's okay.
"Because we love being the underdog, we love being written off as Aussies. We're a small country that takes on the world, particularly in sport. And I kind of like being in that space anyway.
"Any young person can talk about having dreams. I surpassed my dreams probably 20 years ago about what I wanted to do in the game.
"So to be sitting here where I am now just goes to show you that irrespective of where you grow up or whatever barriers you may have, if you kind of believe in something it can happen."
Not that Postecoglou believes he needs to prove a point at Forest, even after being sacked at Spurs - the first time, he explained, such a fate had ever happened to him.
"I don't have to prove anything to anyone … I just believe that you let your actions speak for themselves, and you understand the responsibility you have to provide joy to the most important people, and that is the supporters," he said.
"I guarantee you, if I win things here, people will still have doubts about me because of who I am. And probably same with Nottingham Forest as well.
"But that's why I loved watching the club's recent history, because if you look at clubs who've been promoted in recent years, it's a struggle just to maintain Premier League status. But from when the President (owner Evangelos Marinakis) took over, he's had this ambition, and he's backed it up.
"I'm sure if you asked him, or anyone at the club, they're not trying to prove anyone wrong. They've just got this vision in their head about what they want this football club to be.
"And it's the same with me. I'm not into proving people wrong. I just want to keep doing what I'm doing because it brings joy to people and allows me to live my dreams."
