Ferdinand, 33, has been at Old Trafford for almost a decade but was tipped to leave United this summer after coming under criticism from Ferguson earlier this season, with the Scot claiming he had "lost pace".
The former England captain was told that he was no longer a guaranteed first-choice for United, having previously been so ever since he arrived from Leeds in a then-club record £30 million deal in July 2010.
However, since Nemanja Vidic was ruled out for the season in December, Ferdinand has stepped up again to be the leader of the Red Devils' defence, usually alongside Jonny Evans.
Ferguson now appears ready to reward him with a new contract, though it is believed Ferdinand would need to consider a wage cut from his current figure of £115,000 per week.
"It is all down to how he feels physically himself," Ferguson said with regard to Ferdinand's long-term future at United. "What he is doing at the moment is good.
"He has no issues at all. From time to time, he gets the odd tweak in his back and we have to manage it and look after it. But it hasn't surprised me in the sense that he's still young for a centre-back.
"In normal terms, you would expect a centre-back, with his athleticism, to play well into their thirties anyway. But he had the back problem, so we've had to manage that and by managing it properly, he has adapted really well to it.
"So if you look to last week - I didn't want to play him against Bilbao but, with Jones calling off with 'flu, I played him and he also played on the Sunday against Wolverhampton."
Ferguson is also impressed with the role the 33-year-old has taken on within the squad. He said: "I keep thinking that I signed Rio Ferdinand three or four years ago because I forget he's been here for 10 years now almost, so he has taken on that role of the influential person in the dressing room.
"He's great with the players. If you can keep the players long enough for the influence to spread - because in the modern game, as we know, it's difficult to keep players for more than five or six years - it makes a difference.
"Younger players can take an example off older players in terms of the example set. They learn from the older players."