'Animal' Cristiano Ronaldo was moulded by Roy Keane and other Man United leaders

That's the view of former United assistant manager Rene Meulensteen, who witnessed the teenager morph into a superstar during his first spell at Old Trafford, and has now seen him keep delivering 12 years later.

Having arrived from Sporting Lisbon in the summer of 2003, the then 18-year-old took time to settle and adapt to the physicality of the Premier League.

Yet within four years he was a Premier League winner, the PFA Player of the Year, Young Player of the Year, the Football Writers' Player of the Year and Fans' Player of the Year.

Gone was the scrawny, scruffy urchin with more step-overs than Fred Astaire, instead stood a lean, mean, goalscoring machine.

He certainly lived up to his name and reputation with two goals on his second debut for the Red Devils on Saturday, as he led United to a 4-1 win over Newcastle.

And Meulensteen has told talkSPORT Ronaldo was shaped into the clinical forward fans love and recognise today thanks to his senior teammates from the Sir Alex Ferguson era, with some tough love thrown in as well.

Meulensteen told the talkSPORT Breakfast: "Obviously we had a very, very talented squad back then and a lot of quality, world-class players and a lot of experience.

"Don't get me wrong, he had a high opinion of himself from the moment he walked through the door!

"But, those players like Roy Keane who was there in the early stages and Giggs, Scholes, Gary Neville and Ferdinand all helped him tremendously.

"They kept coaching him from being a player that had a lot of talent, but became more and more functional.

"[They said] 'Cristiano, it is all about helping us winning games.'"

Ronaldo's elite mindset is what has helped him reach and then remain at the very top level ever since that trophy-laden season of 2006/07, when he returned from the World Cup in Germany with Portugal.

Spells at Real Madrid and Juventus heralded personal and collective trophies aplenty, with his incredible stats defying the laws of physics and ageing.

Lee Grant told talkSPORT on Sunday the United squad were reluctant to treat themselves to their traditional 'cheat' meal on Friday before the game against Newcastle - a fixture dominated by Ronaldo and his brace on his second debut.

And Meulensteen insists that drive and determination has been setting the 36-year-old apart ever since he first arrived at Carrington almost 20 years ago.

"He's so determined, so committed," he added.

"Everything that anybody threw at him, not only me but Carlos Queiroz, Mike Clegg from strength and conditioning and Tony Strudwick and Sir Alex Ferguson, he took everything in like a sponge.

"He knew everything to add to make him become the best player in the world, and more importantly, for Manchester United.

"He would take that on board and now he is an established professional footballer that has won many things for club, for country and personal trophies."

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