Italy defender Alessandro Nesta has been ruled out of the World Cup clash against Australia on Monday because of a groin muscle injury.

The AC Milan player was forced off the pitch in his team's 2-0 victory against the Czech Republic in their last Group E game on Thursday, and a scan has confirmed that Nesta will not be available for the match in Kaiserslautern.

However, Italian team doctor Enrico Castellaci believes the player could return in time for the quarter-finals should the Azurri get past the Australians.

"We will try to get him back as soon as possible, we are optimistic," Castellaci said.

Former Everton defender Marco Materazzi, who scored Italy's opener against the Czechs having replaced Nesta, will play alongside Fabio Cannavaro at the heart of defence on Monday.