Eintracht Frankfurt could be forced to start the new Bundesliga season without first-choice goalkeeper Markus Proll.
The 28-year-old will undergo an operation on his ankle after feeling pain during training this week and is likely to be sidelined for around four weeks.
Veteran Oka Nikolov will take over the No.1 spot from Proll and Eintracht coach Friedhelm Funkel insists the long-serving custodian enjoys his complete confidence.
"We have always been able to rely on him in the past," he said.
Meanwhile, Funkel has publicly blasted Brazilian midfielder Caio for his level of fitness following a summer break in his homeland.
The 22-year-old returned to the club overweight and performed miserably in early-season fitness tests.
"I am very dissatisfied," said Funkel. "Caio had to give up at a stage that a player has never given up at before - not even the goalkeepers."