Popovic was appointed last month when Graham Arnold stepped down after starting the campaign with a home loss to Bahrain and an away draw with Indonesia.

Popovic began his reign with a 3-1 home win over China PR last week and said he was "very happy" with four points from his first two games but he also urged his players to "improve in all areas" and cited group leaders Japan as a role model.

"It's not just creativity, we have to improve all over the park because we are aspiring to challenge Japan," said the 51-year-old. "Challenging them regularly as the best team in Asia. To do that we know we have to improve."

Popovic made six changes to the starting line-up that beat China and handed an international debut to 34-year-old midfielder Luke Brattan.

The Socceroos took the lead in the second half when Japan defender Shogo Taniguchi scored an own goal, before Cameron Burgess also put through his own net.

"Hopefully that gives the players confidence moving forward that we're building a foundation," said Popovic. "Hopefully next camp in November we can add some more layers to it."

Australia's next match is home to Saudi Arabia on November 14, before they travel to face Bahrain five days later.

"It's positive," said Popovic. "Every game is difficult, every game is important and Saudi Arabia will be the same.

"It's our home game, we want everyone to get behind us, and to create this type of atmosphere in Melbourne would be special."

Japan head coach Hajime Moriyasu wasn’t overly disturbed with the result, which ended his side’s perfect start to their campaign but still sees them well in control of their destiny.

“To be honest, I wanted to win at home. There were no problems with our overall defence. We conceded because of an own goal, but we weren't broken down overall.

“Despite the Australian team's strong individual and team abilities, the team remained firm and made repeated attempts to break down the opponent's defence, so I commend them for that.”

Japan play Indonesia next on November 15 with China PR to follow four days later, with Moriyasu’s side travelling for both matches.