Cristiano Ronaldo will definitely go down in the history books as one of the best athletes of all time. He will be remembered not only for his success and talent but also for an incredible work ethic and winning mentality.

That's what has driven the Portuguese superstar to continue playing at his best even at 36, defying Father Time as the years go by. Ronaldo has always had high standards in every aspect of his career.

And that probably won't change until the day he retires. That should explain why not long ago he felt disgruntled with his Transfermarkt valuation when he was still playing for Juventus.

Cristiano Ronaldo 'blocked' Transfermarkt on Instagram for his valuation

The website specialized on the transfer market and players' values posted a graphic on Instagram a few years ago with the most valuable starting XI of agent Jorge Mendes' clients. Cristiano Ronaldo was part of it with a €75 million market value.

But the Portuguese forward was apparently not happy at all with his valuation and sent Transfermarkt a private message to complain about it before blocking them. "We can't tag Cristiano Ronaldo because he blocked us after he saw his market value...," the account wrote in the comments of its own post.

Transfermarkt's UK manager Daniel Busch talked to The Athletic about this situation and revealed that Cristiano Ronaldo was not satisfied with his price tag. "We put on a list on Instagram with 10 players 33 and older, and Ronaldo was still in the first place in value, but he said he must be worth much more."

Christian Schwarz, also of Transfermarkt, added that Ronaldo got in touch with the social media team, who tried to explain him he had a high market value for a player his age. "He sent a message first to our social media guys. They answered him, explained why, and told him, 'The people in your age group, you are by far the No. 1.'

"It was £30-50 million difference [between Ronaldo and the next player on the list], and then he sent some similes and then he blocked us." Age might be an important factor to determine a player's value. But not for Ronaldo, who doesn't see longevity as an obstacle to extend his legacy in world soccer.