VIENNA, June 28 (Reuters) - Germany captain Michael Ballack is doubtful for Sunday's Euro 2008 final against Spain because of an injury to his right calf, the German Football Association (DFB) said on Saturday.
Ballack missed training on Friday back at the team's base in Tenero and he was unable to join the eve-of-match session at the stadium in Vienna on Saturday.
'Michael Ballack has not been able to train the past two days,' Germany coach Joachim Löw told a news conference on Saturday.
'On Friday, he had a problem with his right calf, the muscle has hardened and today he couldn't possibly train so we'll have to see how it develops overnight.
'Our medical team will be working with him round the clock but we have to think seriously about alternatives. We could play with (Tim) Borowski or (Bastian) Schweinsteiger in his position.'
The DFB said the question of whether he could play was 'fully open' with just over 24 hours to go before the final.
The 31-year-old midfielder has scored two goals during the tournament and was the outstanding player in the 3-2 win over Portugal in the quarter-finals.
He was less impressive against Turkey in the semi-finals but his absence would be a huge blow to the German team, who are bidding for their fourth European Championship title.
Ballack has never played in a major final for Germany. He missed the final of the 2002 World Cup through suspension and was part of the team that lost the 2006 semi-final to Italy.