German national team captain Michael Ballack has given a decidedly downbeat assessment of his team's readiness for the World Cup  tournament  and says it lacks the experience of the sides that won the 1990 World Cup and 1996 European Cup for Germany.

Ballack, 29, told Berlin's Tagesspiegel newspaper that his team was far less experienced than previous German lineups and still had problems in defence.

"We have a team that is still in development," he said. "We have players who haven't been fielded much by their clubs or in some cases haven't played at all. And don't forget: we no longer have the selection we had in 1990 for the World Cup or at Euro 96 for that matter."

"We had far, far more seasoned players available then, internationally experienced players. These players put their stamp on the teams and thereby on the matches. That isn't the case with our team, it's grown differently.

"This team relies on its enthusiasm and its easygoing spirit. And, of course, it's still making mistakes and isn't that stable yet. That's why I'm going into this tournament with a bit of uncertainty."

Ballack has been nursing a strained calf muscle since taking a knock in last week's friendly against Colombia. But he should be able to play in Friday's opening match against Costa Rica, said team spokesman Harald Stenger. "He's recovering," said Stenger. Ballack had been unable to take part in training this week, sparking fears that Germany would have to start the World Cup without its star.

Ballack said Germany could win the World Cup but made clear he had doubts. "There's a lot I find encouraging. But I'm also saying that a lot can happen both in the positive and the negative sense. The results and performances in the run-up to the World Cup show that this team is still wobbling and isn't that stable."

Ballack also pointed out that Germany's first-round opponent Poland may have lost against Colombia in a recent test match, but it had later gone on to beat a strong Croatian side.

"In the past two years we haven't been able to fully overcome our weakness, which is in defense," said Ballack. "We want to move forward and play fast. That's right in principle, but sometimes we play forward too quickly and lose the ball. We have to make it clear to ourselves that we can't all think in terms of going forward."

Ballack said the pressures on Germany as the host team were tremendous and that he hoped players would cope. "Some 50 or 60 million Germans may be watching us. We hope that players don't clam up and that the team can deliver what it's capable of."