Asano steered home a left-foot volley four minutes before half-time and Ideguchi sealed the victory with a stunning long-range strike after 82 minutes as Japan became the fourth team to reach next year’s finals in Russia.
Despite euphoric celebrations, Japan’s under-fire coach Vahid Halilhodzic — who reports suggested was facing the axe if the Blue Samurai lost — revealed he had considered stepping down before the game for personal reasons.
“The fact is I have a big, big problem in my private affairs,” the 65-year-old told reporters before refusing to answer questions.
“It has nothing to do with football,” added the Franco-Bosnian. “Nobody knew about it but I even thought about quitting.”
A Japan Football Association officials later clarified that it was a “family matter” and confirmed Halilhodzic was expected to travel to Saudi Arabia for their final group game on Tuesday.
Meanwhile, the result dealt a major blow to Australia’s chances of claiming one of the two automatic qualifying spots from Group B after their first defeat in the final round of Asian qualifiers.
The Asian Cup holders get a second bite at the cherry at home to Thailand in their last game on Tuesday when they need to better Saudi Arabia’s result against Japan in Jeddah.
Japan survived a scare after 38 minutes in Saitama when a Mathew Leckie shot deflected off Maya Yoshida against post, before Asano struck a psychological blow shortly before the break.
Yuto Nagatomo whipped in a cross from the left and Asano ghosted in to beat goalkeeper Mat Ryan from close range.
– Curse ended –
Australia threw on veteran Tim Cahill after 70 minutes to try and inject some spark and his industry almost brought an equaliser for fellow substitute Tomi Juric in a goal-mouth scramble.
But Japan effectively ended Aussie hopes of salvaging a point when Ideguchi cut inside to slam a dipping right-foot shot past Ryan from distance for his first international goal.
“I was looking for that kind of a chance and Yuto put in a great ball for me,” said Asano of his opener.
“That’s my job — to try and pinch goals and I’m always ready to give everything for Japan.”
Japan had never beaten Australia in a World Cup qualifier in seven previous attempts but the Socceroos — bidding to reach their fourth straight finals and fifth overall — rarely threatened to extend the curse.
“This is for the wonderful fans and for the people of Japan,” cried Halilhodzic, whose team have an unassailable 20 points from nine games.
Australia and Saudi Arabia have 16 points but the Saudis have a better goal difference.
Ideguchi, meanwhile, appeared lost for words after a wonder strike that looks like sparing Halilhodzic the sack — at least for now.
“I’m just glad it helped us get the win,” he said sheepishly. “Hopefully I can keep working to get myself picked for the World Cup.”
Brazil and Japan’s Asian rivals Iran have already qualified for next year’s World Cup, alongside hosts Russia.
“Obviously, we are extremely disappointed,” said Australia midfielder Jackson Irvine.
“But it’s not finished yet and as long as it’s still mathematically possible we will be giving everything we’ve got.”
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