Adelaide United saw off Brisbane Roar 2-1 thanks to a Ben Halloran brace before Friday's encounter at Coopers Stadium unravelled with a pair of late red cards.

Ex-Roar forward Halloran was on target either side of the interval but substitute Henrique reduced the deficit midway through the second half.

Adelaide defender Taylor Regan was sent off after a VAR replay showed he gouged Stefan Mauk in a melee – an offence referee Jarred Gillett only deemed worthy of a second yellow card.

Mauk was then sent off for a rash challenge on Craig Goodwin, despite the impact of the challenge appearing to briefly leave the Roar man unconscious on the turf.

Before events escalated during the closing stages, Adam Taggart hit the post and passed up another clear chance to put Brisbane ahead.

A groin injury ended Taggart's participation and, after Ken Ilso and Regan hit upright and crossbar for Adelaide, Halloran found the 43rd-minute breakthrough from Goodwin's low cross.

A similar close-range finish four minutes after half-time made it 2-0, although Henrique – who replaced Taggart in the first half – was on hand to convert Dylan Wenzel-Halls' centre.

Tempers then boiled over, with Jordan Elsey's attempts to drag a prone Mauk from the turf following the tackle on Goodwin prompting an angry response from the Brisbane players.

Opposing coaches John Aloisi and Marco Kurz had to be separated on the sidelines, with the latter's Adelaide closing out victory to go two points behind A-League leaders Perth Glory.