Ryan Giggs penned a new one-year deal on Friday, ensuring his United career will extend beyond his 40th birthday. Paul Scholes' future is open to debate given the niggling injuries he has endured, in addition to the knowledge he has already retired once before being talked out of it in January 2012.
Ferdinand seems more likely to sign yet so far, and Ferguson said: "That is a strong possibility. It would have to happen before the end of the season."
Ferdinand is managing a long-standing back complaint and his performances this season suggest he still has a major role to play with the Red Devils, even if England boss Roy Hodgson is not interested.
He is virtually certain to be involved against Real Madrid on Tuesday, when United look to secure their place in the Champions League quarter-finals.
"I think he has had a great season," said Ferguson.
"He has managed himself the right way and we have contributed to that in the preparation we give him.
"He doesn't play every game in the same way that Ryan doesn't play every game.
"But in terms of key matches he has been absolutely brilliant.
"Two weeks ago, against Real Madrid, he was excellent so we need to get him ready for the big one on Tuesday."
Source: PA
Source: PA