Sir Alex Ferguson managed a whole generation of legends across 26 years at Manchester United. But when asked to name his "world-class" players, he only listed four. David Beckham was not among them.

In his 2015 autobiography Leading, co-authored with Sir Michael Moritz, Ferguson wrote a line that stunned the football world:

"In my book there are only two world-class players playing today: Lionel Messi and Cristiano Ronaldo. 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."

About Ronaldo, he added: "And of the four, Cristiano was like an ornament on the top of a Christmas tree."

Who Was Left Out

Ferguson's "world-class" list excluded legends such as Wayne Rooney, Roy Keane, Ruud van Nistelrooy, Rio Ferdinand, Nemanja Vidic and Peter Schmeichel. Players that many would comfortably call world-class did not meet Ferguson's standard.

Asked about defenders specifically, Ferguson defended his choices with a striking historical argument:

"In the last 50 Ballon d'Or awards, only two defenders have ever won it. It's debatable what you'd call Franz Beckenbauer because I would have thought he was a playmaker of the Bayern team and the great German team. The only defender was [Fabio] Cannavaro. He's the only defender who's ever won it in 50 years, so somebody's right — it's all opinion, by the way. It's my opinion and I think I'm qualified to do that!"

In other words, Ferguson's argument wasn't that he was disregarding defenders — it was that the entire football world had been disregarding them for half a century.

Beckham's Response

In 2015, BBC News asked Beckham whether he felt insulted at being left off his former manager's list.

Beckham's response was pure class:

"Not at all. I played for the greatest manager of all time, for the amount of time I did. I was lucky to have played with the players that I did, the team, and to be successful with the club that I loved and still love."

"I tend to agree with the manager, there are certain players that you can call world-class. Thankfully, I played with many of them."

Why Beckham Was Left Out

The relationship between Ferguson and Beckham was complicated. Ferguson believed that in his final years at United, Beckham lost focus due to his status as a global celebrity. At the end of the 2002-03 season, Ferguson decided to sell him — Beckham officially joined Real Madrid on July 1, 2003, for £25 million, after Manchester United had initially agreed a deal with Barcelona.

That same summer, Ferguson moved decisively in another direction. After a pre-season friendly against Sporting CP in Lisbon — in which a 17-year-old winger ran riot against Manchester United's defenders — the Portuguese teenager was on a plane to Manchester within days. His name was Cristiano Ronaldo, and he was given Beckham's iconic No. 7 shirt.

Ferdinand Didn't Take It as Well

Not every legend handled the omission with Beckham's grace. Rio Ferdinand wrote a lengthy Facebook post trying to redefine what "world-class" actually meant:

"Sir Alex Ferguson named 4 players from his time at MUFC as being 'world class' (where was mine among a few other names boss!!). What equates to being world class? Can a defender dominate all types of strikers, can he influence others to perform better, are they vocal, a leader, do they have consistency, perform in big games, are they brave, can they play/pass...?"

He concluded: "Anyway, the debate goes on... Who is WORLD CLASS?!?!? What is WORLD CLASS!?!?!?!"

Many saw it as a wounded reaction — Ferdinand appeared more hurt than he was willing to admit. Beckham, on the other hand, proved that class isn't only shown on the pitch.