For me, saving the distances Federer-Nadal could be compared to Messi-Cristiano.
One of them has more natural talent and would have to lead the historical classification, but the other, because of his ambition, physical and mental strength has managed to match their sport duel so much that in 20 years there will still be fans of Rafa and fans of Roger.
Nadal is a tennis player, but if he had wished he could have been a decent footballer, or a handball player, it does not matter.
He is a very modest person and had always a very spartan way of life where surrender is not admissible.
I think it was Connors who said that Nadal played every match as if he were ruined.
In my case, I am completely biased, I adore Nadal and I think sometimes his tennis quality has been underestimated