Hargreaves injury hell almost over
The 28-year-old England midfielder has had surgery in the United States to combat patellar tendinitis, an inflammation of the tendon that attaches the thigh muscle to the shin bone.
"We'll probably get him into training in 10 days and he should be back at the start of November," Ferguson told reporters before United's Champions League match against VfL Wolfsburg on Wednesday.
"We will take our time because the important thing is to get him playing to the right level. We are in dialogue with him all the time and the physio who was doing his rehabilitation over in America.
"It means we can jointly understand all the treatments and rehabilitation he has been doing."
Hargreaves has had surgery on both his knees and last played for United in a 1-1 draw against Chelsea in September 2008. He has made only 25 starts for the club since joining them in a £17m move from Bayern Munich in July 2007.