Popovic, who was contracted until after the World Cup, has re-signed until after next year's Asian Cup, due to take place in Saudi Arabia between January 7 and February 5.
The announcement on Thursday night (Friday AEST), delivers a timely boost less than 48 hours out from Australia's opening match against Turkey in Vancouver.
"I'm delighted that I will continue to coach the Socceroos through to the Asian Cup," Popovic said in a statement.
"It has been an honour and a privilege to lead the Socceroos, and it is a role that I thoroughly enjoy and one I have never taken for granted.
"My absolute focus right now is on the World Cup."
Popovic took charge in October 2024 and went unbeaten through qualifying to steer the Socceroos to automatic qualification for the first time since 2014.
The early contract call, effectively a six-month extension, is somewhat of a surprise given a strong World Cup campaign would put Popovic firmly in the coaching shop window.
He has long spoken about planning for the Asian Cup and beyond, including testing out young players with an eye to that tournament, which Australia last won under Ange Postecoglou in 2015.
"I'm loving every part of the journey, and every day is a new day, and there's new challenges and it's all exciting," Popovic recently told AAP in camp.
"I do pinch myself sometimes. I'm blessed with the greatest job that you can have.
"It's a group of young men that really have a strong ambition and the staff that wants to help be the best we can be. So I think I'm very fortunate."
The move also gives Football Australia some certainty and stability beyond the World Cup.
"Securing Tony Popovic's contract extension on the eve of the World Cup is a fantastic outcome," chief executive officer Martin Kugeler said in a statement.
"Tony is a world-class coach and he has proven his ability to deliver results while developing talent at the same time.
"While the immediate focus is on the World Cup, this extension provides clarity and enables Football Australia to plan with absolute confidence for the period following the tournament, leading into the Asian Cup.
"Stability and continuity are vital, especially with our exciting, developing young Socceroos squad.
"With the Asian Cup coming so soon after the World Cup, this provides a natural progression and an opportunity for Tony and the team to build upon the positive momentum generated over the past 21 months."
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