The winger has shown his versatility this season, playing in more than one position for the Australian manager.
Postecoglou admitted that Kulusevski was more useful in their current system in central areas.
He stated: “No, not a specific moment. I think I've said before, I think with Deki, the way we get our wingers to play probably doesn't suit him. Not his skillset, more I think his personality. He's just a player who's much more engaged in the game when he's constantly involved. And bringing him to the central area means he's constantly doing that. At times with us last year, when he was on the wing, with the way our wingers play, you're not involved all the time, there's a discipline in keeping your position.
“Sometimes not receiving the ball is part of that process. We put our wingers where we do to pin back oppositions. I could see he was, not frustrated, he just wanted to give more. So obviously towards the back end of last year we played him inside a couple of times, you could see him growing into that. Certainly from the beginning of pre-season this year, it was always the intention to bring him inside and let him develop. And he has, and he's improving, that's the key thing. It's not like he's just gone inside, he's actually working on his game, areas where he can hurt the opposition, working on the defensive side of his game, because it's a little bit different to playing out on the wing. I think he's enjoying, which obviously helps in terms of his own development.”
He added: “I looked at his background obviously, when he was growing up and when he first broke into the first team, that was his position. It's not that he can't play out wide, he got sort of put in that position because he was effective out there, when he played, particularly in teams that played counter-attacking football, which allowed him then the space to run at people.
“I think you could see why he'd go out there. But some of it is just the natural development of players. There's plenty of wide players who end up playing inside because their game develops and they understand more about it. I think he's one of those.”
On how Kulusevski can improve further, he finished: “Like I said before, that's exactly my point: just constant improvement in everything. There's nothing he does that he can't improve in. Deki, we're talking about ambition, if you speak to him, he's got pretty lofty ambitions for himself as a player, and what he can do. With that kind of mindset he can improve in all facets of his game. He's already very, very effective for us. With and without the ball. The exciting bit is that I think there's a lot more to come.”