Manchester City defender Micah Richards fears the worst after pulling a hamstring in England U21's 4-0 win over Denmark.
Richards was forced out of the action after less than three minutes in Viborg.
Head coach Stuart Pearce said: "He's got a hamstring problem and he's diagnosed himself as being out for four weeks - that's Dr Richards for you.
"That could be four days though, as that's him diagnosing himself!
"Let's hope for Manchester City's sake and the preparation in the summer that it's not too long."
A four-week absence would rule Richards out of the FA Cup semi-final with rivals Manchester United.
