Chelsea doctor Bryan English has revealed they're working closely with Germany's medical team to help Michael Ballack get back to full fitness.
He told Chelsea's website: "We are in constant dialogue with the German medical team and every stage of Michael's rehabilitation has been and will continue to be with the full co-operation between club and country.
"There is still some way to go before Michael can return back to full training and we will continue to monitor his injury situation on a daily basis during these final weeks of his rehabilitation."