Australia missed out on a place in the men's 4x400m relay final after finishing fourth in their Olympic heat on Thursday.
Led by 400m individual finalist Steven Solomon, Australia was in fifth heading into the final lap but couldn't squeeze into a qualifying top-three spot.
They finished sixth in a time of three minutes 3.17 seconds.
But they got bumped up to fourth when Venezuela and the Dominican Republic were disqualified for changeover infringements.
Venezuela later successfully appealed their DQ to make the final, meaning Australia officially finished fifth in the heat.