(Image: Getty Images)
Mooy, linked with former Australia boss Ange Postecoglou and Celtic in the summer, would get on the end of the rebound but his goal-bound finish was hacked off the line.
But despite the late Aussie push in the first period it was Japan that went in at the break a goal to the good.
National legend Keisuke Honda said he was shocked to see Kyogo begin on the bench but the former AC Milan man will have been pleased to see his introduction on the hour mark.
But Japan were pegged back minutes later in bizarre style.
A rash challenge prompted a penalty decision from Qatari referee Abdulrahman Al-Jassim – and Hibs star Martin Boyle was ready to ram home from 12 yards.
Harry Souttar of Australia and Kyogo Furuhashi of Japan
(Image: Getty Images)
But just as Boyle was preparing to run up, he was told to stop when VAR changed the call to a free-kick as replays showed the foul was outside the box by a matter of inches.
It didn’t matter, however, as Ajdin Hrusic smashed the set-piece in off the bar and Japan’s lead vanished.
So it was on Kyogo to rescue the match but he could only look on as several of his team-mates squandered a bonkers goalmouth scramble with Wataru Endo getting three bites at the chance and Socceroos keeper Mat Ryan making a fabulous double save.
He then floundered when through on goal but with just four minutes to go he tried to follow up Takuma Osano's chip, which clipped the post and bounced yards from the line.
The Celtic hero raced in for the final touch and forced Behich to turn the ball into his own net.
The drama in Saitama has revitalised Japan's challenge in the third phase of AFC World Cup qualifying.
Australia remain top in Group B with nine points after four games but Japan are three behind them and Saudi Arabia.
The first two finishers qualify for Qatar 2022 automatically while Kyogo's country face a play-off with the other third placed finishers in Group A as it stands.
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