The 22-year-old defender was due to play for Germany in a friendly clash against Australia on this Tuesday evening but, having suffered a knee injury, he was sent for a scan in Dusseldorf which showed up meniscus damage and he may need surgery to get the problem repaired.
Boateng is due back at City on Tuesday morning, where he will be assessed further by the club's medical staff, with a view to finding out the extent of the damage and the best course of action.
However, it is likely that City boss Roberto Mancini is set to be deprived of another defensive player, having already lost Micah Richards to a hamstring injury, while Kolo Toure is sidelined indefinitely as he awaits the outcome of his failed drug test.
It means City will be without three first-team defenders for the Premier League games against Sunderland and Liverpool, as well as the FA Cup semi-final against Manchester United on April 16.
At the moment only Richards looks to have an outside chance of being fit for the United clash at Wembley, he is reportedly having an oxygen chamber installed at his house in an effort to accelerate his recovery.
"I will do anything and everything to be ready for the United game," Richards said. "I knew straight away what I had done because I heard the dreaded 'ping'. It is a bit sore, but I'm hoping it is not too bad."
Mancini should at least be boosted by Argentinian full-back Pablo Zabaleta's return to City after he was given compassionate leave to visit his critically ill father in his homeland.