Bruce Kamau slotted home a 38th-minute opener and Bruce Djite made it two five minutes after half-time when Michael Theo parried a Kamau shot into his path.

Another rebound completed a superb outing for Guillermo Amor's men, with Pablo Sanchez turning home when Djite was denied a second nine minutes from time.

United sit a point above the Roar and three shy of table-toppers Western Sydney Wanderers.

Melbourne Victory and Sydney FC extended their winless runs to five and six matches respectively after sharing a 1-1 draw at AAMI Park.

Kosta Barbarouses broke the deadlock a minute into the second half but Sydney overcame Jacques Faty's straight red card for hauling down Besart Berisha to level in the 76th minute – David Carney firing home from Rhyan Grant's corner.