Cahill scored three times inside 37 minutes while skipper Mile Jedinak also struck on Tuesday night to send Australia to the top of their qualifying group ahead of main rivals Jordan, who are two points behind and play Kyrgyzstan in Bishkek early on Wednesday (AEDT).
It was all one-way traffic in favour of the Australians, who easily controlled possession despite struggling to move the ball around freely on the long-grassed surface.
At times Ange Postecoglou’s team were sloppy against their lower-ranked opponents – an off touch here, a wayward ball there.
But Aaron Mooy shone bright as usual with a hand in every goal, and whenever he found space – and there was acres of it – the aerial threat of Cahill was waiting.
There was not a Bangladeshi defender in sight for the former Everton man’s first when he nodded in a deep free-kick from Mooy on six minutes.
It was nearly half an hour later before the Melbourne City star also set up the second with a through ball to debutant Josh Risdon, the in-form Perth Glory defender crossing for Cahill to volley home.
Five minutes later Australia’s all-time leading goalscorer added another to his total by adding the finishing touch to a cross from Mooy, who had latched onto a sublime through ball from the recalled Matt McKay.
Crystal Palace midfielder Jedinak got in on the action anyway just before the interval with a textbook header from close range after Bailey Wright headed across the box.
If the first half was a raging goal fest, the break gave way to tedium.
Postecoglou replaced James Meredith with Jason Davidson and brought on Tommy Oar and James Troisi for Mooy and Massimo Luongo.
The crowd perked up briefly as the home side made a couple of inoffensive swoops forward, while Jedinak went close again 10 minutes from time.
But his tremendous overhead kick was parried to safety by Bangladesh keeper Sahidul Alam.
Postecoglou was satisfied with his side’s four first-half goals in Dhaka but admitted to being unimpressed with a sloppier second-half showing, believing they are nowhere near their best.
However, he cut his players some slack, acknowledging that the “unusual build-up” amid security concerns in Bangladesh had taken its toll on the playing group.
“Knowing what the boys have been through the last few days both physically and mentally, we lost our focus and concentration in the second half and it became very, very scrappy,” Postecoglou told Fox Sports.
“When that happens it’s not about goals, it’s just that we didn’t really maintain our composure.
“But with everything that’s gone on, the players and the staff have handled themselves impeccably and we’re pleased we got through it unscathed.”
The Socceroos left Bangabandhu National Stadium for the airport almost directly after the match as part of the heavy security measures in place, with Football Federation Australia opting for the team to spend little more than 24 hours on the ground to protect their safety.
A smattering of Australian fans were among the boisterous near-packed crowd, despite advice from the Department of Foreign Affairs and Trade to exercise a high degree of caution in Bangladesh.
With the final qualifying fixture of the year now done and dusted the pressure is firmly back on Jordan, whose 1-0 loss to Kyrgyzstan in Bishkek early on Wednesday (AEDT) leaves them on 13 points – two points behind Australia.
The battle for top spot will likely come down to a winner-takes-all showdown between the pair in Australia early next year.
But either way the Socceroos are in a strong position to at least progress as one of the four best second-placed teams from the eight groups.
Despite the Socceroos’ fizzling form, Postecoglou said the victories against both Bangladesh and Kyrgyzstan in Canberra last week were the perfect remedy to their 2-0 loss to Jordan.
“I can’t fault the players in terms of getting a reaction after the last disappointing result and performance against Jordan,” he said.
“We’re nowhere near where we want to be, and we’ll keep moving along until we get to be the team that we eventually want to end up as.
“But it was a good 10 days, we exposed more players to this level and others came back in.
“With any luck, by the time March comes around we’ll have a really strong contingent of players competing for spots.”
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