Ricardo Carvalho has lifted the lid on why Cristiano Ronaldo and Kylian Mbappe have reached the very top of the game and maintained remarkable standards that few can hope to match.
The former Portugal international defender spent many years playing with five-time Ballon d'Or winner Ronaldo, savouring Euro 2016 glory along the way, as well as spending three seasons together at Real Madrid.
Carvalho has seen Ronaldo at the peak of his career, with there no sign of the 36-year-old icon allowing his powers to wane any time soon, and is not surprised to have seen the modern-day great retain a standing at the pinnacle of his profession.
What has been said?
Carvalho told FourFourTwo when asked if the world sees the real Ronaldo: "I think people do now, yes.
"He's grown a lot over the years and is much more mature. One thing hasn't changed, though: his whole life revolves around being successful in anything he does.
"Cristiano is a perfectionist. He doesn't demand anything from you that he can't do himself.
"People may criticise him and disagree with him, but there's no question that as a footballer, he's Portugal's biggest symbol worldwide - and by his own merit, he has been in that position for many years already."
What about Mbappe?
Upon leaving Ronaldo and Real behind in 2013, Carvalho took the opportunity to link up with Ligue 1 side Monaco.
It was while at Stade Louis II that he first came across a precocious talent that would go on to make a similar impact on a global stage as Ronaldo once did.
Mbappe is, at just 22 years of age, a four-time title winner in his native France and a world champion from 2018.
On the obvious potential that continues to be unlocked by a man in the final year of his contract at Paris Saint-Germain, Carvalho added: "He's a five-star person.
"The best thing about football is when you meet kids like him who become idols for a bunch of people, and then you realise that he hasn't changed a bit from that boy you knew. This is Mbappe.
"It was incredible to see a talent like him emerging. We had a good relationship, and recently, when I was Marseille's assistant coach, we played PSG in the French Super Cup. He came over to our bench to give me a hug.
"At Monaco, everything we spoke about had the sole purpose of helping him improve.
"When you're starting out and have the traits he had, you can be more individualistic than you should, so it was important for him to improve his decision-making.
"He always wanted to do more, and felt that he could, but it's crucial to find balance for the team. That was how he reached this level."