Australia's Andrew Tye and Mitchell Swepson delivered a spirited bowling performance as the tourists defeated Bangladesh by three wickets in Saturday's fourth Twenty20 international to record their first win in the five-match series.
Bangladesh took an unassailable 3-0 lead in the series with Friday's 10-run victory in Dhaka.
The final match will be played on Monday at the same venue.
Tye (3-18) and Swepson (3-12) restricted Bangladesh to 104-9 as the hosts lost three players, including skipper Mohammad Mahmudullah to a duck, with opener Mohammad Naim top-scoring with 28 runs.
The Bangladesh bowlers fought hard to defend the measly total but Australia's Dan Christian's 15-ball 39 coupled with team mate Ashton Agar's run-a-ball 27 helped the visitors seal the contest with an over to spare.