Huntelaar is being treated by an eye specialist after rupturing a blood vessel in his left eye.
He needs to be given the all-clear to return to training with his club, but no time limited has been placed on his return.
Dutch coach Louis van Gaal commented earlier in the week that it was "nothing really serious", but the German club's general manager Horst Heldt seems to disagree.
"Something like this can be good in two days, but it can also take considerably longer," said Heldt.
- Sports & Recreation
- Eye Care