"Cristiano has been doing excellently and he is well ahead of schedule. The specialist was surprised the condition he was in," Fergie said.
"The next three weeks he will have rehab and then the next part will be endurance work and serious running, before he goes into the football side with us.
"There has been no problem, his progress has been great. He has never missed a session morning or afternoon.
"We are pencilling him in for the beginning of October."