In an ominous message to overlooked incumbent captain Lucas Neill, coach Postecoglou says he's taken the first steps to create the next "golden generation" of Socceroos.
Neill and fellow stalwart Brett Holman were snubbed in Postecoglou's regenerated 23-man squad for the next week's friendly against Ecuador in London.
Other golden oldies such as Mark Bresciano and Josh Kennedy were also absent as Postecoglou plumped for a younger batch of players he wants to form the backbone for Australia's World Cup campaign and beyond.
"If players do well in this game and back it up with a strong second half of the year, certainly they will be in pole position (for the World Cup)," Postecoglou told reporters on Wednesday.
"There is no point waiting any longer.
"It doesn't necessarily mean the door is shut on the other players. But ... good form in a good competition will not be ignored."
Postecoglou said Neill, 35, wouldn't be surprised by his omission, having just signed a deal with Watford but yet to play for the England Championship club.
Tim Cahill appears set to assume the captaincy, though Postecoglou wasn't interested in the leadership debate.
"I don't know what the fascination with the national captain is," he said.
Postecoglou said Holman, 29, was close to selection while Bresciano was just returning from a FIFA suspension and striker Kennedy's season in Japan had yet to start.
"If you look at our experienced players or players at the top end of their careers in age terms, there aren't many who are playing at the highest level, if any," he said.
"From that perspective, it makes sense to me to start looking at building a new core in the team."
Four newcomers - Curtis Good (Dundee United), Chris Herd (Aston Villa), Massimo Luongo (Swindon Town) and Ben Halloran (Fortuna Dusseldorf) - could debut for the Socceroos after joining a squad Postecoglou said "represents the first steps in what I believe is the building of the next golden generation for Australian football".
"I have had a good look around in terms of our landscape," said Postecoglou.
"There is a group of footballers now embarking on their careers both here and more predominantly in Europe. And the time has come to give them an opportunity at international level."
The Ecuador friendly on March 5 is the Socceroos' last match before May, when Postecoglou must name a preliminary 30-man squad for the World Cup.
Australia must nominate its 23-man squad for the World Cup on June 2, some 11 days before its opening match against Chile.