Portsmouth midfielder Kevin-Prince Boateng has apologised to Michael Ballack for the challenge which ruled the Germany captain out of the World Cup.

Boateng, who will represent Ghana - an opponent of Germany in the group stage - at the World Cup this summer, told Germany's Sport Bild magazine that he had already offered his apologies several times to Ballack.

"All I can do is apologise," said Boateng, who is the half-brother of Germany international Jerome Boateng.

"I was just too late and I hit him straight on.

"It looked stupid. I apologised to him twice on the field and now for a third time.

"I am sorry. It was not intentional."

Ballack is still letting the realisation sink in that he is going to miss the World Cup due to the ankle injury he picked up from the tackle.

"Of course I am angry and it is disappointing. I don't want to comment on it yet," he said.

"When you get such a diagnosis just two or three weeks before a World Cup then it is bitter.

"But that is football. Things must go on. I am obviously disappointed and have just got to let it sink in."