Ronaldo was keen on a move to Spanish giants Real Madrid.
Ferguson said: “I think the fans understand the situation — he was a young man tempted by the lure of money.
“Since we gave him our decision he has accepted it and his training has been fantastic.
“He’s come back from his ankle operation ahead of schedule and been the perfect patient.
“Cristiano has been training every day until 5pm and shown real determination to get back playing.”
He added: “There has been no toys thrown out the pram. He has accepted the situation and got on with it.
“I’m delighted he is back. You are talking about a truly magnificent player.”