Wednesday's win came five months after Bangladesh secured their first test win over Sri Lanka and a month before the first anniversary of their maiden triumph over England in the longest form of the game.
Seventeen years since granted the test status, there are still whispers whether Bangladesh belong in the elite group but skipper Mushfiqur Rahim remains satisfied with the progress the team has made under his leadership.
"If you look at our home performance, it has been pretty consistent," he said. "Against England also, we were very close in the first test and beat them in the second test. That's the belief we have."
Shakib articulated that belief in a pre-series media interaction where he said Bangladesh were capable of winning both the tests against Australia and the opening triumph has filled Mushfiqur with similar optimism.
"Hopefully we'll come harder at them in the next test and hopefully we'll seal the series," the captain said.
Counterpart Smith believed Australia paid the price for a poor first innings display, especially since they had to bat fourth on a track where the ball both bounced unpredictably and turned viciously.
"It was a great test match, credit to Bangladesh the way they played," Smith said.
"We probably let ourselves down in the first innings with the bat, probably should have made a few more there. It was pretty difficult batting here in the second innings and I thought we did pretty well to get 240 in the end."
Bangladesh's three-pronged spin attack claimed 19 of the 20 Australian wickets to fall with Usman Khawaja's run out in the first innings the only victim to elude the slow bowlers.
Australia will slip one place to fifth in the test rankings even if they level the series by winning the second test in Chittagong from Monday. A second defeat would see them drop another place.