Adelaide United will host the A-League Grand Final after they thrashed Melbourne City 4-1 on Friday.

Guillermo Amor's side finished top of the league standings and will now play the championship decider at the Adelaide Oval for the first time against either Western Sydney Wanderers or Brisbane Roar.

Bruce Djite curled in a fine opening goal from 25 yards early in the second half, before he buried a penalty into the bottom corner to double the lead after Jack Clisby tripped Bruce Kamau in the area.

City grabbed a lifeline when Nick Fitzgerald swept into the far corner after Connor Chapman teed him up from a clever short corner, but Dylan McGowan headed home Marcelo Carrusca's corner to restore Adelaide's two-goal cushion in the 88th minute.

And substitute Pablo Sanchez sent the majority of the 15,000 fans into raptures in injury time as he volleyed Djite's deep cross past Thomas Sorensen from a tight angle to make it 4-1.

Wanderers and Roar, who finished just a point behind Adelaide in the table, meet on Sunday in the second semi-final.