Since moving to the Premiership from Bayern Munich in 2006, Hargreaves has been suffering with long term injuries in both knees, which limited his participation to just 15 league starts with United.

"Hargreaves had the operation on Monday and it went well, although we won’t know the exact details until he gets back. He has to have a further operation on his left knee in a few weeks," Manchester United manager Alex Ferguson said.

"Unfortunately he is out for the season, but we hope this will now be put to bed and we’ll get him back as a fit player for the start of next season."

The 27-year-old has only featured three times for United so far in the season, and now is in the United States for the double-surgeries.

"The reason for us sending him out to America was because the medic there is a first-class specialist who deals with these sorts of injuries, and Owen's own preference was to be in Colorado," added Ferguson.

It is worth noting that Canadian born Hargreaves has played 42 times for England.