Sir Alex Ferguson has admitted Manchester United were left with no option but to send Owen Hargreaves for a career-saving knee operation in America.
Hargreaves has not been pain free since arriving at Old Trafford from Bayern Munich last year.
Although there have been times when the 27-year-old has been able to play for extended periods, including last season's Champions League final win over Chelsea in Moscow, Hargreaves still experienced discomfort in both knee caps.
After missing another pre-season and being limited to just three appearances this term, Hargreaves was forced to accept a course of injections from a specialist in Leicester was having no effect.
And, following a meeting with renowned knee surgeon Dr Richard Steadman in Colorado, Hargreaves has been forced to go under the knife in a bid to cure the problem.
''We have exhausted every other way of dealing with the situation,'' said Sir Alex Ferguson. ''We have tried to manage it by sending him to a specialist in Leicester for a series of injections.
''Their success rate is very good. Unfortunately it wasn't good enough for Owen because he was still feeling great pain in his knee caps. We had to look at the next stage and that meant sending him for an operation.''
Hargreaves has had one operation and will return to Canada for a short spell before having a second.
Then he will begin a lengthy rehabilitation programme that Ferguson hopes will result in the £18million midfielder being able to prove he was an astute signing after all.
''It is going well so far,'' said Ferguson. ''The surgeon is very pleased with it and we had a physio there who was happy as well. We hope it will get rid of the problem and he will come back a new player.''