With it's ACL campaign due to start later this month, the win for the under-achieving Adelaide side was perfect timing whilst the loss ended any hopes of Brisbane making the finals.
Fabian Barbiero gave Adelaide the lead after only seven minutes, getting on the end of a precise cross from Matthew Leckie.
Brisbane struggled to make an impression in pursuit of an equalising goal in a scrappy first half from both sides.
Lucas Pantelis sealed the victory for the Reds soon after the interval with a clinical finish from the edge of the area.
Matt McKay's 82nd minute red card rubbed further salt into the wounds of Ange Postecoglu's side, who are now four points behind Newcastle with only one match remaining and therefore out of contention for a place in the finals.