Chelsea have been working closely with Germany's medical team in a bid to get the international back to full fitness.
And Ballack told Germany's Premiere TV: "It looks good for my comeback. I expect that I will be fit again and be playing this year.
"The problem was that I was told the injury would take three or four weeks so I kept working towards my comeback every week and waited for the pain to ease. That took a while.
"It is always frustrating for a player if you don't know when the injury is healed.
"But I am thinking positive right now because the pain is almost gone."