Croatia coach Zlatko Kranjcar is confident his side has what it takes to defeat Australia in Stuttgart tomorrow and claim a spot in the knockout stages of the World Cup.

It has not been a convincing campaign for the Croatian side, losing creditably 1-0 to Brazil before struggling to a 0-0 draw against Japan.

But despite going 180 minutes without a goal, Kranjcar believes his side have the firepower to defeat Australia.

"Our plan is to play the same as we did against Japan and Brazil, to play offensively," he said. "We just hope that the players use the chances better than they have the two games before."

Kranjcar has been forced to make a major change in defence with Juventus' Robert Kovac unavailable after picking up his second yellow card in the tournament, against Japan.

Stjepan Tomas will be called up to mark his good friend and Australia skipper Mark Viduka in the match.

Kranjcar said that Tomas was the logical replacement for the younger Kovac brother, and that his friendship with Viduka had no influence on his decision.

"Kovac had the two yellow cards, so Tomas comes in for him," he said. "It just happens that Tomas and Mark are very good friends. I was their coach at Dinamo Zagreb (in the late 1990s).

"For the 90 minutes, they can put their friendship to one side, and I'm confident Tomas will come out the winner against Viduka."

The other change sees CSKA Moscow striker Ivica Olic come in for the out-of-touch Ivan Klasnic.

"Yesterday I named the first starting XI, and I said Olic would substitute Klasnic," the Croatian manager said. "He (Klasnic) won't start tomorrow, he'll start on the bench and will come on if necessary."

Australia has surprised many at this World Cup, overwhelming Japan 3-1 in Kaiserslautern and troubling Brazil in Munich before going down 2-0.

Kranjcar said that while the Socceroos have big-name players, it is their consistency across the pitch which has helped them this campaign.

"For the Australian side, Viduka, (Harry) Kewell and (Marco) Bresciano are the most dangerous players, but they are collectively very good and a strong team as a whole," he said.

He also was glad Harry Kewell was freed from a disciplinary hearing by FIFA, insisting he wanted his men to play the best Australian team available.

"I'm very happy that Kewell is playing tomorrow so they can play their best starting XI," he said. "Then if we win, the victory will be rated even higher."

With Stuttgart boasting the largest Croatian community in Germany, Kranjcar believes the extra crowd support could be the factor that gets Croatia the three points and a spot in the next round.

He added: "It feels like home in Stuttgart. We are expecting maybe 30,000 Croatian spectators here. We are the home team for this match, and I'm expected the crowd to be very much in favour of us."