Hasan Mahmud took a career-best 6-55 as Bangladesh bundled Australia out for 198 to take the honours on the opening day of the first Test in Darwin on Thursday.
At the close Bangladesh were 96-1, 102 runs behind Australia.
Mominul Haque was on 35 with Tanzid Hasan alongside him on 32 as the visitors made a superb start to a test match most people expected them to lose inside three days.
Earlier, Hasan led an impressive display by the visitors' seamers as Australia slumped to their lowest test score against Bangladesh, their previous worst being 217 in Mirpur in 2017.
The 26-year-old was the pick of the attack, but he was ably supported by fellow quicks Taskin Ahmed and Ebadot Hossain, who took two wickets apiece.
"I was just trying to bowl line and length, trust the process and follow what the captain was saying," Hasan said.
"(Taskin and Ebadot) were trying their best and they did very well also."
Steve Smith was the only Australian to offer any resistance, scoring 71, while the rest of the batsmen looked out of sorts against the disciplined attack.
"We haven't played a test match for a while and it can take some time to get into it," Smith said.
"It wasn't easy. The ball was doing stuff and you have to be patient.
"Perhaps we got dragged into a few we didn't need to, but that's the pressure."
AUSSIES SLUMP
After skipper Pat Cummins chose to bat on a perfect Darwin day, a full-strength Australia were expected to dominate a Bangladesh side who were well beaten by a Cricket Australia XI in their only warm-up match.
Hasan made the initial breakthrough in the 12th over with the score on 45.
Jake Weatherald, on 23, had a huge swipe at a ball outside off stump and only managed a thick edge to wicketkeeper Litton Das.
Hasan struck again soon after, fellow opener Travis Head chopping on for 22 to leave Australia 52-2.
Bangladesh then saw a huge opportunity go begging when Smith, on two, edged Ebadot to third slip where Tanzid Hasan spilled the chance.
Smith had a second escape next over when he got a thick edge off Taskin only for the ball to fly through a vacant third slip.
Marnus Labuschagne, on one, wasn't so fortunate.
He poked at an Ebadot ball outside off stump and edged to Bangladesh captain Najmul Hossain Shanto at second slip, leaving Australia 61-3.
Cameron Green came in and played some big shots before chipping Taskin to short midwicket, where Mushfiqur Rahim took an easy catch.
Wicketkeeper Alex Carey looked in good touch after lunch and cruised to 19 until he played on to Ebadot with the score on 129.
Taskin then produced the ball of the day to beat Beau Webster's bat and clip the top of off stump to leave the home side struggling on 152-6.
Cummins tried to steer the hosts to tea without further loss, however Shanto brought Hasan back into the attack with immediate success, the Australian skipper getting a big edge to Litton.
Hasan got his fourth in the same fashion, Mitchell Starc getting a thin edge to the keeper with the score on 172.
Smith threw his wicket away going for a big hit before Nathan Lyon was last man out in similar fashion.
Bangladesh started their reply confidently and eased to 36 before Australia got the breakthrough, Shadman Islam (20) getting a leading edge off Mitchell Starc to Lyon at backward point.