Owen Hargreaves could be back playing in four weeks.

The Manchester United midfielder has been out of action for a year after deciding to undergo operations on both knees in an effort to solve his tendinitis problems.

Hargreaves has done all his rehabilitation work in the United States so far under the guidance of renowned knee surgeon Dr Richard Steadman.

However, the former Bayern Munich star returned to United's Carrington training complex earlier this week to take the next major step in his bid for recovery.

Hargreaves has not done any ball work yet and Sir Alex Ferguson does not expect him to for a short while as the United medical staff complete a handover that will take the 28-year-old back into their care.

But the United boss is optimistic that, if all goes to plan, Hargreaves could be back in a United shirt at some point next month.

"I feel it will still take us four weeks to get him into the rhythm of training again and get to the point of match play," said Ferguson.

"Normally, when a player has been out for that length of time he is helped by the fact he is doing his rehabilitation with other players.

"Because he did it on his own in the USA, under the guidance of Dr Richard Steadman, it is not easy.

"But he has the determination and resilience to see it through. He is now back with us and hopefully the boy gets a break and continues his progress without any further mishaps."

As this kind of operation is still quite rare, there must be some doubt over Hargreaves' chances of making a full recovery, or getting back to the level that saw him win 42 caps for England, the last of which came against the USA in May last year.

But Ferguson takes comfort from the growing number of players that have come back from formerly career-threatening cruciate knee ligament surgery, the latest being Chelsea's Joe Cole.

"We don't see the fact he has been out a year as a handicap," said Ferguson.

"Other players have been out a similar length of time.

"When Joe Cole came back on Wednesday you forget he was missing for nine months. It is achievable, particularly when they are young.

"He is not kicking a ball yet. The physio who attended to him over there will stay here for a week for the changeover.

"He and our physios are discussing exactly at what stage he is at but he should be into football training quite soon."