Both sides started their campaigns with wins but it's Australia who stand on top of the table after their 3-1 defeat of Japan while the defending champions squeezed past Croatia 1-0.

"They are a good side," said Barcelona superstar Ronaldinho.

"We expect a tough match, they defend well and are good when it gets physical.

"We will have to pay attention to all of their players so that there are no surprises.

"It will be a tough physical match -- that's their style."

Brazil coach Carlos Alberto Parreira has been plotting hard to see off the Aussies, who came from behind to see off Japan for their first ever finals victory on Monday.

The Brazilians by their own exalted standards did not come out of their shell as they edged Croatia with a Kaka goal.

On Friday, Parreira put his squad through their tactical paces, the session concentrating on turning defence into attack and urging a constant flow of passes to feed strike duo Ronaldo, now over the sickness he felt after the Croatian game, and Adriano, who similarly did not shine on day one.

The session saw Emerson take a linchpin role as he sought to spread passes out to Ronaldinho and Kaka.

On his own form Ronaldinho admitted that he also had room to improve.

"I know I need to do better," he told reporters.

"But the Croatians marked us very well."

Skipper Cafu said the team were ready to meet the Australian challenge after discussing the Croatian showing.

"We've talked a lot about where we are. Even during the Croatian match we were making adjustments. Then we talked about it again in Thursday training and carried out exercises to tighten up on marking,"

As Cafu tried to get forward to bolster a flagging Brazilian attack unable to improve on Kaka's first-half strike -- one cross almost provided a goal for Ronaldinho -- he left spaces at the back as a result and that forced a reorganisation as Adriano dropped back.

Ronaldo's ineffectiveness saw him withdrawn and Real Madrid clubmate Robinho introduced.

"We've been concentrating hard on improving this transition of the marknig system," according to Cafu, who expects the Australians to pose a different kind of challenge.

"They have a very fast and dangerous player in Mark Viduka and Marco Bresciano is very mobile. Also, they play three at the back unlike four as with the Croatians."

Midfielder Ze Roberto dubbed Australia "very strong in the air as they have tall players who know how to put themselves about. We will have to treat them carefully. We know it will be a tough game."