Melbourne City's Michael Zullo out for rest of A-League season

Michael Zullo will be sidelined for up to 10 weeks with an injury to his big toe as Melbourne City prepare to face Adelaide United in the A-League's final round.

Melbourne City's A-League title push has suffered a hitch, with Michael Zullo ruled out for the rest of the season with a toe injury.

City had been sweating on Zullo's fitness since he limped off during Sunday's 3-2 away loss to Perth following a heavy collision with Josh Risdon.

With his team preparing for their pivotal final-round clash with Adelaide at AAMI Park, coach John van `t Schip revealed the 27-year-old utility had undergone surgery on Wednesday and would be sidelined for eight to 10 weeks.

"It was something with his big toe and is connected with the joint," van `t Schip said on Thursday.

It's the latest in an unlucky run for the 10-time Socceroo, who made just one 46-minute appearance in the first 12 rounds of this campaign due to calf problems and missed a year before that with an anterior cruciate ligament injury.

"It's been for him very disappointing with those setbacks," van `t Schip said.

"But it's something that is part of his season and he has to just make sure he gets back at a good level when he comes back in full fitness."

Zullo's injury means van `t Schip will be forced to make at least one change to his starting line-up against the Reds, in a match that will go a long way to determining their finals position.

A left-back by trade, Zullo had been deployed more in midfield of late, although he was shifted back to defence in Perth.

Ben Garuccio appears the obvious replacement having plugged that gap recently, but van `t Schip is saying little about his plans.

The coach was wary of Adelaide's "fluid" all-round game as fourth-placed City attempt to finish the last round with a win to shore up their chances of claiming a maiden Premiers Plate.

City join Brisbane, the Reds and Western Sydney in the hunt but are the least likely of the four contenders to claim the minor premiership.

Previously shoo-ins, Sunday's capitulation to Perth Glory handed the inside running to the Roar, meaning even with a win over United on Friday, their hopes will then hinge on John Aloisi's outfit losing to Melbourne Victory and the Wanderers losing to or drawing with Wellington.

"Maybe with a bit of luck, we could have a result at the end of the weekend that could give us something special," van `t Schip said.

"But we also know it's not in our hands."

Melbourne City are undefeated at home in the A-League since round eight but will be facing an Adelaide side who have just set an A-League record of four consecutive away clean sheets.