AUSTRALIA'S chances of making a fourth consecutive World Cup are hanging in the balance after suffering a damaging 2-0 loss to Japan at Saitama Stadium.
Japan took the lead in the 41st minute after Takuma Asano whipped home a perfectly executed cross, before a long-range rocket from Yosuke Ideguchi sealed the result nine minutes from time.
Having secured its first qualifying win against Australia in six attempts, Japan booked its spot at a sixth-straight World Cup.
But what Australia's destiny is remains to be seen, with so many different permutations remaining.
Tied on 16 points with Saudi Arabia, the Socceroos remain third in Group B with a goal difference of +4, trailing the Saudis' goal difference of +6.
The Socceroos must win and win big against lowly Thailand at AAMI Park on Tuesday night to give themselves their best possible chance of avoiding the dreaded playoffs later this year.
Saudi Arabia hosts Japan in Jeddah on Wednesday morning (AEST).
An Aussie win against the Thais means the Saudis have to beat Japan and then again surpass our goal difference.
But the Green Falcons will know exactly how many goals they need to win by.
Ange Postecoglou was dealt a blow before the match when Huddersfield star Aaron Mooy was ruled through illness.
Without the key midfielder it took the visitors six minutes to get their first solid stint on the ball, but after that it was mostly one-way traffic.
By the 25-minute mark Australia had registered 70 per cent possession and, when on the ball, it was clear the instruction from Japan's bench was to sit off.
The tactics worked too, as was the case for the first half in Melbourne when these teams met last year. Postecoglou at one stage went ballistic on the bench after a lengthy possession stint in defence ended in a long ball erratically spraying out.
It was a match that at times lacked fluidity, which should be no surprise given the high stakes.
But what was clear was that Postecoglou was dead serious about his pre-match warning not to get too physical.
The unseasonably cool 21 degree conditions were perfect for a high-tempo pressing game, but the Socceroos weren't given the opportunity to implement it by the Samurai Blue.
In the 38th minute Australia went desperately close to taking the lead after a goal-bound Mat Leckie shot took a wicked deflection, only to hit the post.
And three minutes later they found themselves behind after Asano found was left inexplicably free on the penalty spot.
Yuto Nagatomo, under pressure from Leckie, was able to still swing in a pinpoint right-footed cross that caught the defence out and saw Brad Smith left stranded by his man.
Tim Cahill came on in the 70th minute for Tom Rogic and was roundly booed, given his history of terrorising Japan.
But he could only watch on as Ideguchi slid by Jackson Irvine and lashed the ball into the top corner from the top of the box.
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