The 29-year-old made his first start since September 2008 in November but lasted just five minutes before leaving the pitch with a hamstring problem.
He has not played since and manager Alex Ferguson said the player had been sent to Munich, where he used to play for German champions Bayern before moving to Old Trafford in 2007 for 17 million pounds ($26.64 million), to see a specialist.
When asked if Hargreaves could ever play again consistently for the club, Ferguson told a news conference on Monday: “We’re all concerned. He hasn’t played for over two years.
“You would have to be a super optimist to think everything will be rosy for him in terms of making comebacks. What we’re really trying to do is help the lad, that in itself is the biggest challenge … To try and help him get back to a level where he can still play football.”
ormer England international Hargreaves’ career has been cursed by chronic tendinitis in his knees which has required surgery. His United contract runs until the end of this season.
