Captain Craig Moore is suspended after collecting five yellow cards, while injury has robbed the squad of Danny Tiatto, Bob Malcolm and Charlie Miller, with a question mark also over Ivan Franjic.

"Danny tried really hard and he's training okay but he's just not right, and Charlie has done a minimal amount of work this week, so they're both out," Postecoglou said.

But he insisted that despite the disruptions Roar could still get a result if they worked hard.

"We've just got to battle through it," he said. "The reality of it is we've lost three games in a row and we've got to stop that.

"It's going to be a tough game in Sydney. They had a bit of a hiccup last week but they're a good side, they've been probably the most consistent out of all the teams this year.

"Your efforts got to be there every week and it's going to be a tough ask but from another point of view, if you do go there and get a result it gives you a massive confidence (boost) going into the following week."

But the injuries and suspension have opened the door for Andrew Packer to return to the squad to face his old side this weekend.

"Everyone has written us off and it is going to be tough," Packer admitted. "I think it's fair enough, we've got a lot of guys out, we've lost Moorey  this weekend and it is going to be a tough ask.

"But we'll be going there to get a result and, who knows, we can come away with the three points, definitely."

He added: "The last couple of weeks have been tough with the change of coach and the shock of losing Frank Farina, but this week you can see we've really turned it around.

"The new gaffer's come in and he's really put his own stamp on the place and it looks really good.

"The guys that maybe didn't get a chance before have stepped up and we senior guys know we've got to be on our game. A new coach brings challenges for everyone and I think it's been fantastic."