The hosts climbed above Sydney and Central Coast Mariners to fourth as Fabio Ferriera, Sergio Cirio and Bruce Djite all scored to eclipse Matt Thompson's effort.
In an action-packed clash that saw some excellent strikes, a series a fiery confrontations and even a streaker, the visitors were comprehensively outplayed for almost the entire game.
United took a deserved lead with 14 minutes gone, Ferriera collecting Marcelo Carrusca's pass before slotting home.
And that advantage was doubled nine minutes after the interval as Cirio tapped in a loose ball from close range.
An unlikely comeback was on the cards when substitute Thompson was set up brilliantly by Nikola Petkovic to rifle past Eugene Galekovic.
But, by the time Dijte made it 3-1 in the 88th minute, the undisciplined visitors had picked up five yellow cards on their way to a convincing loss.
