Ferguson: Cristiano Ronaldo, Cantona, Giggs, Scholes my world class players

Sir Alex Ferguson says he worked with just four world-class players at Manchester United -- and Wayne Rooney, Roy Keane and David Beckham were not among them.

The Scot nominated Eric Cantona, Cristiano Ronaldo, Ryan Giggs and Paul Scholes as the quartet who were at the very highest level, as he also omitted Ruud van Nistelrooy, Peter Schmeichel, Rio Ferdinand and Carlos Tevez from his select list.

Ferguson preferred Cantona, the catalyst when United won the league title for the first time in 26 years in 1993, and Ronaldo, who scored 42 goals in their Champions League-winning campaign in 2008.

Giggs became the most decorated player in the history of English club football under Ferguson, winning 13 Premier League titles and two Champions Leagues, and making 941 of his record 963 appearances during the Scot's time in charge.

Fellow one-club man Scholes played 718 times under Ferguson, who told the BBC's Football Focus: "They made the difference and the evidence is there. When we brought him [Cantona] in we won the league that season -- it was his mere presence and his ability to make and score goals.

"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."

Ferguson said he managed other "great" footballers but explained: "These players elevated themselves above that."

The 73-year-old omitted Rooney from his final games in charge in 2013 after claiming the striker, who is the third highest scorer in United's history, had asked to leave the club.

Keane, who was United's captain from 1997 to 2005, has been a regular critic of Ferguson's since his time at Old Trafford ended in acrimonious circumstances with his contract ripped up.

Beckham, who has always praised Ferguson, took the corners that led to both of United's injury-time goals in the 1999 Champions League final but was sold to Real Madrid in 2003.

Ferguson has rebuilt his relationship with Van Nistelrooy, who scored 150 goals in five seasons, since his departure in 2006, while Tevez annoyed United by joining Manchester City in 2009.