Ferguson has revealed he will finally quit as United boss within the next three years and although Gill insists he has not been told that by Ferguson himself, he conceded United could follow in Liverpool's example with an internal appointment when the Scot does step down.

Gill told BBC Radio Five Live's Sportsweek programme: "We are making sure our squad is continually reviewed and improved as necessary and the age of the squad is right so that, when Alex does decide to retire, anyone taking over has a fantastic squad with the right age profile. We also have an assistant manager who will be very much in the frame in Carlos Queiroz."

He added: "He's clearly a key part of our success. If you look at what Liverpool achieved in their very successful years during the '70s and '80s (that) was through internal appointments.

"Carlos is a key factor in all the success we've achieved over the last couple of seasons."

Regarding the specifics of Ferguson's eventual departure Gill continued: "We haven't discussed that.

"I think his guiding principle over whether he stays is whether he is healthy and still has the desire, which I'm sure he will have.

"It's still three and a half years away, we will look at it at that time."

Ferguson has already gone back on one promise to retire but insisted he will not be managing at Old Trafford by the time he reaches 70 in December 2011.

"I won't be managing here any more than three years at the very, very most. Without question. I can assure you of that," the 66-year-old said.