Coach Holger Osieck kept Asian World Cup qualifying rivals Japan guessing as to whether Tim Cahill will start for Australia in Tuesday's crucial clash in Brisbane.
The clash of Asia's top two ranked teams in Group B heads the bill among four regional qualifying games Tuesday, with South Korea and Iran looking for home victories in Group A.
Everton midfield dynamo Cahill has proved a thorn for Japan in past encounters with the Socceroo netting both goals in Australia's 2-1 home win during qualifying for the last World Cup.
Cahill became the first Australian player to score at a World Cup finals tournament with two late goals in a memorable 3-1 victory over Japan in Germany in 2006.
Osieck left Cahill on the bench as Australia were held to a scoreless draw by Oman in searing temperatures in Muscat on Friday and there have been calls for the return of the team's talisman, who has 24 goals in 55 internationals.
But the cagey German was giving little away at Monday's official pre-match press conference on whether Cahill will play.
"There is always the slight possibility for a change and we're having another training session in the afternoon and I'll have a close look at the other boys who didn't start in the Oman game," Osieck said.
"Looking at our group, everybody on the list could be on the pitch. I haven't decided yet and Tim is definitely always an option for the starting eleven."
Skipper Lucas Neill said Japan were favourites following their flying start with two home wins and nine goals against Oman and Jordan.
"They have had better preparation, two home games and now they come here with confidence," Neill said.
But he added: "We like the underdog tag. We know we're in for a very tough game but one that we believe we can win.
Japan's Italian coach Alberto Zaccheroni plans for the Blue Samurai to run the Socceroos off their feet.
"If we can play like we are doing at the moment at a fast tempo, I am convinced we can play well not only against Australia, but any team," Zaccheroni said.
Japan beat Australia in extra time in the 2011 Asian Cup final and on penalties in the 2007 Asian Cup quarter-finals.
Iran, who have made the World Cup finals three times, take on Qatar in Teheran looking to build on their controversial 1-0 win over Uzbekistan in Tashkent.
Substitute Mohammad Khalatbari scored the winner for Iran in the 94th minute after the Uzbeks claimed to have earlier had the ball over the line in an incident missed by the referee
Midfielder Mojtaba Jabari will miss the home tie through illness and Ali Karimi is expected to play in a more advanced role for Iran, marshalled by former Portugal coach Carlos Queiroz.
South Korea will look to remain unbeaten in Group A with a home match against Lebanon after beating Qatar 4-1 in their opening game in Doha.
The 2002 World Cup semi-finalists bounced back from a goal down to see off Qatar to put them on course for an eighth consecutive World Cup finals appearance, stretching back to Mexico in 1986.
Iraq will look to take full points against Oman in Doha to keep up with Japan and Australia in Group B.
Iraq, the 2007 Asian Cup champions, began their bid for a second World Cup finals appearance with a 1-1 draw away to Jordan, while the Omanis, under Frenchman Paul Le Guen, were encouraged by their goalless draw with Australia in which they had the bulk of the play.
