In his latest book, Leading, which is released on Tuesday, Fergie identifies the four players he considered to be best among those who wear a red shirt during his time at Old Trafford.
Ferguson singles out Ryan Giggs, Paul Scholes, Eric Cantona and Cristiano Ronaldo as the four standout performers of his 26 years at the club.
“They made the difference and the evidence is there,” he told the BBC’s Football Focus.
“The younger breed like Ryan and Scholes were just fantastic players and the thing about those two was longevity.
“Are there players who have played right through the whole of the Premier League and performed at the level they have? There are none, absolutely none.
“Of course Ronaldo was just a complete genius of a player.”
Tellingly, while the former United manager conceded he had worked with other “great players”, there was no mention for the likes of Roy Keane, Rio Ferdinand, David Beckham, Peter Schmeichel or Wayne Rooney.