The midfielder, who returned to first-team action against Liverpool in the Carling Cup on Wednesday night for the first time in eight months, insists he is grateful for all the club's efforts to get him back to fitness.
The Germany captain was quoted as saying he had been dismayed by the treatment he received from Chelsea as he struggled to recover from two ankle operations.
Now Ballack has made it clear he wants to repay the club's medical team for all their hard work over the last eight months.
He said: "I was surprised and disappointed when I read the words I was supposed to have said.
"The Chelsea medical department has made its best possible efforts. I am very grateful for the work that everyone has done - in particular the physios - over the last couple of months in order to get me finally back on the field.
"Now I am ready to repay all their hard work by doing my best for Chelsea.
"I would also like to thank the fans for their support and patience - it has meant a great deal to me."