Ferguson: I only had four world-class players at Man Utd - and Cristiano Ronaldo was the best

Speaking at an event to promote his new book, ‘Leading’, Ferguson narrowed the field of genius to just four men: Eric Cantona, Ryan Giggs, Cristiano Ronaldo and Paul Scholes.

Wayne Rooney, David Beckham, Roy Keane and Rio Ferdinand are among the players not to get a namecheck by Ferguson, but his use of the term is very restrictive.

And even in such a small club, one man stood out above all the rest.

“In my book there are only two world-class players playing today: Lionel Messi and Cristiano Ronaldo,” said Ferguson at an event at Royal Festival Hall.

“I don't mean to demean or criticise any of the great or very good footballers who played for me during my 26-year career at United, but there were only four who were world class: Cantona, Giggs, Ronaldo and Scholes.

“And of the four Cristiano was like an ornament on the top of a Christmas tree.”

Ferguson also discussed a number of transfer targets who never arrived at United, including Sergio Aguero and Mario Balotelli.

The Scot also explained how the club let Paul Pogba slip through their hands as he joined Juventus for £800,000 compensation in 2012.

“There are one or two football agents I simply do not like,” Ferguson writes. “And Mino Raiola, Paul Pogba’s agent, is one of them.

"I distrusted him from the moment I met him. He became Zlatan Ibrahimovic’s agent while he was playing for Ajax, and eventually he would end up representing Pogba, who was only 18-years-old at the time.

“We had Paul under a three-year contract, and it had a one-year renewal option which we were eager to sign. But Raiola suddenly appeared on the scene and our first meeting was a fiasco.

"He and I were like oil and water. From then on, our goose was cooked because Raiola had been able to ingratiate himself with Paul and his family and the player signed with Juventus.”