Whipped into shape by coach Niko Kovac's German-style discipline, Croatia believe they can beat five-time champions Brazil in the opening game of the World Cup next month, despite a raft of recent injuries.

In the space of just a week, three players in Kovac's provisional 30-man squad have gone down with injuries and will miss the summer's big sporting extravaganza, including QPR midfielder Niko Kranjcar.

"That's too much, it's not good," Monaco goalkeeper Danijel Subasic told AFP at the team's training camp in eastern Austria.

"After that, I hope we're done with injuries."

Aside from Kranjcar, defender Ivan Strinic and striker Ivo Ilicevic have been ruled out of the tournament.

But Kovac can still count on the likes of Real Madrid's Luka Modric, fresh from Champions League glory, Bayern Munich's Mario Mandzukic and captain Darijo Srna when he names his final squad on May 31.

"I think the guys who are going to replace them and play instead of them are going to do a good job," noted Panathinaikos's Gordon Schildenfeld.

"(But) they're quality players so of course we're going to miss them."

First up, Croatia face none other than tournament hosts and favourites Brazil in the opening game on June 12.

But the team in red-and-white chequered shirts are undaunted by the proposition.

"It's a dream game... it's going to be a really difficult game but I think we have quality even to win that, to cause a surprise," said Schildenfeld.

Croatia's opponents will have a country of 198 million behind them, but "sometimes pressure can affect you in a bad way so I hope it's going to be like that," he added with a grin.

His teammate Sammir agreed: "We can draw or maybe even win because Brazil usually go slowly into the tournament, they play better and better with each game so it's not bad to play against them in the opening match, with huge pressure."

For the Brazilian-born Getafe player, there will be no conflict of interest playing in the country of his birth: "I'm going there to represent Croatia, I'm going there thinking I'm going to work, to play football, to give my best for our team."

Croatia finished third in the 1998 World Cup in France but failed to qualify for South Africa last time around.

Now, thanks to some tough love from German-born Kovac, 42, who took over the team just eight months before the finals despite little managerial experience, the players feel confident.

"Physically, it's hard," Subasic said of the new training regime.

"It's a German mentality... more discipline, more organised" and very different to the Croatian way, he joked.

"But that's good for us."

Security concerns in Brazil have seen some of the players already advise their families to stay at home.

"I don't want to have somebody there, to think, is everything ok every day... so it's better like this. My mind will be 100-percent concentrated on football," said Schildenfeld.

Aside from Brazil, Croatia face Cameroon and Mexico in their Group A matches.

"I think we have quality, we have a really good team, we all play in good clubs, we're always the best when we don't have any other choice," noted the Panathinaikos player.

"So I think you can expect the best from Croatia."