A former Manchester United coach has highlighted Cristiano Ronaldo's ego as being a key part of his success.
The five-time Ballon d'Or winner made his professional debut all the way back in August 2002, coming on as a substitute for Sporting CP in a UEFA Champions League encounter against Inter Milan.
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What followed were stints at the Red Devils, Real Madrid and Juventus, with the Portugal international scoring plenty of goals and winning silverware wherever he went.
While he may now be 39 years of age, Ronaldo is currently playing an important role at Saudi Pro League giants Al Nassr, helping the side as they aim to compete at both domestic and continental level.
The attacker recently achieved the brilliant feat of scoring more than 900 goals for club and country, and will be looking to add as much as he can to bolster that tally.
Rene Meulensteen, who coached the Portugal captain during their time together at United, has explained how the forward has been able to maintain such high levels throughout his career.
"It's true that Cristiano Ronaldo's ego has been the key to his lasting success, and that's in a good way, he refuses to ever let his standards drop," Meulensteen told BoyleSports, per GOAL.
"He would never turn up to training and give anything less than his maximum effort and you can see that is still the same now at 39 years of age.
"He'd never even sprint at 70%, he is all or nothing and has worked so hard on the pitch as well as on his brand, he has a billion followers and he can do whatever he wants next.
"He does everything to the best of his ability and always pushes his own standards forward."
While other players have changed their positions on the pitch in order to prolong their careers, Meulensteen feels this is something the former Los Blancos star would not do.
"Cristiano Ronaldo will choose to retire when he feels he can no longer play at the very top, he is never going to drop deep and play in another position," the Dutchman added.
"His passion for the game and to play for his country is exemplary.
"It's just unbelievable, really, and we've been very fortunate over the last almost 20 years that we've had players of the ilk of Cristiano and Lionel Messi.
"They drove each other to such a high level and both have been absolutely world-class.
"I can only speak for Cristiano because there was a short spell in his career in which I worked with him.
"I think everything he's achieved he has deserved because only himself was always the main motivator behind all his success."
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