Manuel Neuer could make his Bayern Munich comeback in the DFB Pokal final if coach Jupp Heynckes decides he is fit to return.
Neuer, 32, has not played a competitive match since undergoing surgery in September and has yet to resume full training with the World Cup less than six weeks away, but last month returned to light training for the first time in seven months.
However, he did not train with the team last week, staying in Munich to work in the gym while the rest of the squad flew to Madrid for the Champions League match against Real.
Bild reported that Neuer had suffered a bone edema -- a build-up of fluid in his left foot -- adding another delay to his comeback.
Bayern, who sealed their sixth successive Bundesliga title last month, face Eintracht Frankfurt in Berlin on May 19 as they chase a 12th domestic Double.
Back-up goalkeeper Sven Ulreich said he is happy to let Germany captain Neuer play if he is ready, telling kicker: "I would love to play in the final. I've had a good season and helped us reach the final.
"But if Manu is fit and the coach says that he is playing then that that's the way it is. I understand that Manu needs playing time -- it's important, too, for the national team."
Heynckes said on Friday that Neuer has "great ambitions to go to the World Cup" as he continues his recovery.