Former Manchester United manager Alex Ferguson on Sunday said Lionel Messi is purely a Barcelona player but believes Cristiano Ronaldo would be a success anywhere in the world.

The Barcelona and Real Madrid forwards have won the last seven Ballon d'Or awards between them, marking the pair as the two best players of their generation and among the greatest to have ever played the game.

Ferguson said: "Ronaldo is tough. People say 'who is the player in the world' and plenty of people quite rightly say Messi.

"You can't dispute that opinion. But the thing about Ronaldo, Ronaldo could play for Millwall, Queens Park Rangers, Doncaster Rovers or anyone and he'd score a hat-trick. I'm not sure Messi could do it."

Ferguson, who managed Ronaldo for six years before the Portugal international left Old Trafford for the Santiago Bernabeu in 2009, has backed his former protege as the more complete footballer.

"Ronaldo's got two feet, he's quick, he's good in the air and he's brave, though Messi's brave too, of course. I just think Messi is a Barcelona player," said the 73-year-old Scot.

Ferguson also labelled the 30-year-old as the player who advanced the most under his coaching over his 26 years in charge of United.

"Ronaldo is the biggest improvement I ever had at Manchester United really because he came as a young skinny kid at 17.

"And yes, he had stuff such as diving which people used to criticise him but, once he got out on the training field, he was fantastic," the retired coach said.

Ferguson says nothing would make him happier than watching another manager eclipse his trophy haul at Man United.

The Scot amassed 38 trophies in 27 years at United, creating a dynasty that shaped the Premier League era for years. His phenomenal success led to a stand being named after him at Old Trafford and a bronze statue of him being erected outside the ground.

No top-flight British manager has lifted silverware as many times as Ferguson, but he says winning is in the fabric of the club and there would be no sour grapes from him if anyone surpassed his achievements.

"We had a wonderful run of success when I was here and we won a lot of trophies," he told the Sunday People.

"But I really hope someone comes along and breaks my record here, I really do.

"I'd like to see another United manager come in and win 45 -trophies in 25 years. Nothing would make me happier.

"Why? Because it's a food chain at this club. First there was the great Sir Matt Busby and then there was me.

"Now I'd love someone else to come in and establish a long run of success because that's what this club is all about."