Michael Ballack of Chelsea is attended to by medical staff after being tackled and fouled by Kevin-Prince Boateng of Portsmouth during the FA Cup final match between Chelsea and Portsmouth at Wembley Stadium on May 15, 2010 ((Laurence Griffiths/Getty Images) )

Injured Germany captain Michael Ballack says he will decide on his national team future after the World Cup.

Ballack will miss the tournament in South Africa because of an ankle injury. The 33-year-old Chelsea midfielder told the German news agency DPA he would try to return to football as quickly as possible.

Speaking to DPA at Germany's training camp on Sicily, Ballack also said he expects to extend his contract with Chelsea, which expires this summer.

"I want to play football again as soon as possible," Ballack told DPA Tuesday, one day after being ruled out of the World Cup. He is expected to be sidelined for about eight weeks after tearing ligaments in his right ankle.

Ballack was injured in Chelsea's 1-0 victory Saturday over Portsmouth in the FA Cup final in a tackle by Kevin-Prince Boateng.

"I assume that I will be fit for the start of the new season," Ballack said.

Ballack said whether he returns to the national team for the 2012 European Championship was one of the questions he would have to consider during his summer break.

"I have to think about some things and sort them out. That had been in the pipeline anyway," Ballack said.

'Important step'

Ballack flew to Sicily Monday to join the national team and will stay there until Sunday.

"It's the best for me. It's an important step to be with the team and give them support now," said Ballack, who has played 98 games for Germany.

Meanwhile, Ballack's lawyer and agent Michael Becker said he was considering legal steps against Boateng for what he said was a premeditated foul with intent to injure.

Boateng, who was born in Berlin and played for Germany's under-21 team before deciding to make himself available for Ghana, the homeland of his father, apologized his action.

"I can only apologize," Boateng told Sport Bild's online edition of his late challenge.

"I apologized twice on the field and now for the third time. I am sorry. It was not intentional," Boateng said.

Boateng's half-brother Jerome is a defender for Germany.

Ghana is one of Germany's Group D rivals at the World Cup.