Manchester United fans could never have predicted what Cristiano Ronaldo would go onto achieve when he signed for the club in 2003.
After his stunning pre-season performance for Sporting Lisbon, it was clear that Ronaldo had incredible talent but nobody knew he'd eventually become one of the sport's greatest ever.
Ronaldo would spend a further six years at Old Trafford, scoring 118 goals and winning nine trophies, before making a then world-record move to Real Madrid.
Football fans know the rest of the story with Ronaldo breaking every record under the sun at the Bernabeu and inflating his Ballon d'Or tally to an almost unprecedented total of five.
However, it was those early days at Old Trafford that made him the sporting great he is today and all the weeks of hard work at Carrington were simply invaluable.
Ronaldo's Man Utd spell
The Portuguese's incredible work rate has been documented by former teammates in the past, with Ronaldo doing everything in his power to become the world's best.
And that sentiment has been corroborated by Quentin Fortune who opened up about Ronaldo during an interview with the Independent.
The South African spent seven years with United and has discussed how Ronaldo had the elite mentality from the start, including upon his arrival to the dressing room.
Ronaldo's dressing room introduction
Fortune remarkably recalled Ronaldo's entrance, noting: “Ronaldo came with so much confidence, it was unbelievable.
“He walked in the changing room and basically told everyone he’s the best. Not in perfect English but you could make it out.
“That set him above all the young players and he could back it up with his work ethic and ability. Even at that age he wanted to be better at everything. If you did something in training he’d practise and come back and do it.”
How many players would sign for United, meet the rest of the squad and call themselves 'the best'?
Well, it goes to show that Ronaldo had incredible belief from the very start and when he left the club six years later, he more than backed up his opening statement.
And when he possessed that talent that he did, Fortune insists that senior players such as Roy Keane and Gary Neville didn't mind his cockiness in the slightest.
“Cristiano might have been walking around saying he’s the best – yes, he was cocky – that was just Ronaldo.
"And once a young, or any, player backs it up in the game, there isn’t a question mark.
“He couldn’t have asked for a better foundation and support. And together, oh my goodness, those two would rule the world. It was a perfect combination.”
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