The Australian squad has been preparing for Thursday morning's (AET) game at Nelspruit's Mbombela Stadium and goalkeeper Mark Schwarzer knows they'll face a strong opponent when they line up for the decider.

"We already know that technically they're a very good side and they've obviously got a big aerial threat up front with the big boy (Nikola Zigic)," Schwarzer told Fox Sports.

"They're reasonably solid at the back as well, so they're going to be a difficult team to play against."

He continued: "Some of the guys have played against the Serbian team before at the Olympics and know if you put a bit of pressure on they might tend to crumble a little bit. So we're going to try and do that.

"We have to go for it, we need the win and we're going to give it everything we can."

Socceroo Mark Bresciano added the Australians were feeling confident despite claiming just one point from their opening two matches.

"It's a massive game for us tomorrow night, there's still a lot of confidence, you have to have a bit of confidence to get into this game to try and get a result," he said.

But Bresciano admitted qualifying for the next round would be difficult for the Socceroos who need the Ghana-Germany result to go their way.

"Just a win isn't going to do it for us, but that's the only thing we can control, so we're just going to go out there and win and see what the other result is at the end of the day," Bresciano said.

Nevertheless, if the Socceroos do pull off a miracle and qualify for the Round of 16, the Melbourne-born midfielder believes they can continue on in the tournament.

He added: "I think it'd be a pity if we don't get through this next game and onto the next round, because I think the further we go, the better we're going to get."

Schwarzer continued the Socceroos were ready to go after a few days of preparation following Saturday's 1-1 draw with Ghana.

"We had a good couple of days after the Ghana game to really prepare and to really recover from the game firstly and prepare for the Serbia game," the Fulham shot-stopper said.

"We're going to go into the game with quite a bit of confidence."