Postecoglou took over from Holger Osieck in October 2013, lowering the average age of the squad considerably and orchestrating a respectable performance in a daunting group at the World Cup in Brazil.
The men in green and gold have endured a tough run of late, losing to Japan and Qatar and drawing with the United Arab Emirates in their final friendlies before hosting the Asian Cup in January.
But the increased scrutiny on Postecoglou's work to date doesn't faze the man in charge, who claims he is relishing a tough task ducked by Pim Verbeek and Osieck.
"There's a reason previous coaches didn't do what I'm doing. Because they kind of knew this was going to happen and wanted to avoid it," he told Fox Sports.
"I'm not going to avoid it.
"The questions are all legitimate," he added, referring to doubts about the Socceroos' latest results.
"I go back to why I was initially appointed. It's not just about me. The organisation (Football Federation Australia) needed us to regenerate and change the style of football. I'm going to fulfil that mission as long I'm in charge.
"The Australian sporting public, the football public and certainly the people who appointed me knew what they were getting. For me to start changing now ... I've worked really hard with this group of players and the staff to make them believe in something. If you make someone believe in something the worse thing you can do is take that away from them at the most critical time."
Asked if he would consider approaching the Asian Cup with more of a 'safety-first' game-plan, Postecoglou reiterated an unswerving belief in his preferred methods.
"There's certain basic, core principles that I believe I won't ever deviate from because that's what made my team successful. It won't shift for any short-term gains. That's the coach I am.
"There are core principles I will not waver on. I like my teams to have more possession than the opposition and I like my teams to be proactive. Simple as that.
"My coaching methodology is not based around aesthetics or what people want to see, it's based around winning. That's all I've ever done."
The coach baulked at suggestions Australia should be expected to overcome the majority of their Asian rivals on a regular basis.
"You cannot underestimate any opposition," he said.
"One thing I get annoyed with is people say, 'we should be beating certain teams'. That doesn't exist anymore. Not just here, in world football."
The run of poor friendly results has already seen Australia fall to their lowest ever FIFA ranking and they are set to drop further when the latest figures are published.
But Postecoglou isn't concerned about his team's position on a table, looking instead to the prize of reaching and competing meaningful at the next World Cup in Russia.
"Rankings are not what is driving us," he said.
"What's driving us is to create a team and create a structure and foundation for us to be successful on a consistent basis. So that in four years' time when we go to a World Cup, we aren't the lowest ranked team.
"We will go to the World Cup, I have no doubt about that.
"That should be our goal always," he said, when asked about the Socceroos run to the knockout stages of the 2006 tournament.
"But that won't happen by just me saying that."
The men in green and gold have endured a tough run of late, losing to Japan and Qatar and drawing with the United Arab Emirates in their final friendlies before hosting the Asian Cup in January.
But the increased scrutiny on Postecoglou's work to date doesn't faze the man in charge, who claims he is relishing a tough task ducked by Pim Verbeek and Osieck.
"There's a reason previous coaches didn't do what I'm doing. Because they kind of knew this was going to happen and wanted to avoid it," he told Fox Sports.
"I'm not going to avoid it.
"The questions are all legitimate," he added, referring to doubts about the Socceroos' latest results.
"I go back to why I was initially appointed. It's not just about me. The organisation (Football Federation Australia) needed us to regenerate and change the style of football. I'm going to fulfil that mission as long I'm in charge.
"The Australian sporting public, the football public and certainly the people who appointed me knew what they were getting. For me to start changing now ... I've worked really hard with this group of players and the staff to make them believe in something. If you make someone believe in something the worse thing you can do is take that away from them at the most critical time."
Asked if he would consider approaching the Asian Cup with more of a 'safety-first' game-plan, Postecoglou reiterated an unswerving belief in his preferred methods.
"There's certain basic, core principles that I believe I won't ever deviate from because that's what made my team successful. It won't shift for any short-term gains. That's the coach I am.
"There are core principles I will not waver on. I like my teams to have more possession than the opposition and I like my teams to be proactive. Simple as that.
"My coaching methodology is not based around aesthetics or what people want to see, it's based around winning. That's all I've ever done."
The coach baulked at suggestions Australia should be expected to overcome the majority of their Asian rivals on a regular basis.
"You cannot underestimate any opposition," he said.
"One thing I get annoyed with is people say, 'we should be beating certain teams'. That doesn't exist anymore. Not just here, in world football."
The run of poor friendly results has already seen Australia fall to their lowest ever FIFA ranking and they are set to drop further when the latest figures are published.
But Postecoglou isn't concerned about his team's position on a table, looking instead to the prize of reaching and competing meaningful at the next World Cup in Russia.
"Rankings are not what is driving us," he said.
"What's driving us is to create a team and create a structure and foundation for us to be successful on a consistent basis. So that in four years' time when we go to a World Cup, we aren't the lowest ranked team.
"We will go to the World Cup, I have no doubt about that.
"That should be our goal always," he said, when asked about the Socceroos run to the knockout stages of the 2006 tournament.
"But that won't happen by just me saying that."