Captain Ballack injury doubt for Germany

(CNN) -- Germany captain Michael Ballack is a doubt for Sunday's Euro 2008 final against Spain because of a calf injury.

The midfielder missed their training session in Vienna on Saturday to receive treatment at the team's hotel.

"We have to see how it develops overnight," Germany coach Joachim Loew told the Associated Press.

"They are working around the clock on him."

The German football federation said that Ballack also missed the session on Friday, held at their training camp in southern Switzerland.

That session had not been open to the media.

"It was unthinkable that he would have been able to train today," Loew added.

Ballack, 31, has been a key figure in Germany's march to the final but has been troubled in the past by calf injury, missing the opening game of the 2006 World Cup with a similar problem.

He also had to sit out the 2002 World Cup final against Brazil because of suspension.

Chelsea's Ballack has scored two goals in Euro 2008, the highlight a blistering free kick against Austria in a group mach and the third goal in the 3-2 quarterfinal win over Portugal.

Germany had earlier received good news about Ballack's fellow midfielder Torsten Frings, who said he was fit for the final after a rib injury.

Frings featured in Germany's opening three matches but he was forced to sit out his side's quarterfinal victory over Portugal after suffering a broken rib in the last group game against Austria.

The vastly experienced Werder Bremen player returned to action during Wednesday's semifinal against Turkey, after being sent on at half-time by coach Joachim Loew to counteract the early dominance of their opponents.

The move helped, with Germany much more effective after the break before going on to win the clash in Basel 3-2, although it remains to be seen which team Loew starts with against Spain.

Frings' battling qualities in the heart of midfield could prove invaluable to the Germans, particularly if Ballack is sidelined, as they look to combat a Spanish side whose confidence is sky high heading into the clash at the Ernst Happel Stadium.

Luis Aragones' side have been victorious in their last 11 matches and are unbeaten in 21, with their latest triumph being Thursday's 3-0 defeat of Russia in their semifinal encounter.

The absence of tournament leading scorer David Villa through injury is a blow for the Spanish, but his loss could see Aragones further bolster an impressive-looking midfield with the selection of Cesc Fabregas.

With or without the Arsenal midfielder, Frings believes Spain's midfield is a class apart from most other teams. "They have a strong, technically-gifted team capable of cutting through the midfield like no other side," said Frings.

"We will have to put them under pressure and prevent them from getting into the game, otherwise it could prove very difficult."

Spain's current form, combined with some inconsistent German displays over the last few weeks, means that for many people the Iberian nation are favorites to win their first major title since their European Championship success in 1964 this weekend.

Frings admits his side have not been at their best throughout the tournament, but he was warned his side's critics to write them off at their peril.

"You can accuse us of a lot of things but this much is clear: we have had an answer to everything that's been thrown at us so far and that's why we are in the final," he said on www.uefa.com.

"During the group phase certain things were not working and, because of that, the coached changed the system, which worked very well against Portugal. It's important now that we learn from what went on during the Turkey game."

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