Navas joined PSG in the summer after providing the platform for three UEFA Champions League final victories with Real Madrid. The Costa Rica international has played alongside and against some of the world's best players, notably Cristiano Ronaldo and Lionel Messi in five seasons in La Liga.

Yet the 32-year-old has still been impressed by Mbappé, who — at 20 — has already established himself among the creme de la creme of the world's football elite.

WATCH: Mbappé dominates the Classique

"He's a very young player, but he's already achieved some things that men of his age don't usually achieve. Since I arrived here, I've seen a happy guy who loves his football, who's very humble. I like how he lives his life, how he behaves towards his teammates and how he sacrifices himself on the pitch for the team," said Navas, who saw Mbappé net his seventh goal in just four outings with PSG in Friday's Ligue 1 Conforama defeat in Dijon.

"We all know just how gifted he is: very quick and intelligent, his movement is good and he's very clinical in front of goal. He's an incredible young man, very complete, probably the best of his generation."

Though born in the Paris suburbs, Mbappé broke through at AS Monaco, and after 16 goals in 41 top-flight appearances — including 15 in 29 league games in his breakthrough season of 2016/17 — he returned to the capital as one of world football's biggest and most promising talents.

"What Kylian Mbappé does isn't a surprise," said French legend Zinedine Zidane, Navas' former boss at Madrid and the man who has to work out how to stop Mbappé when the sides meet in this month's UEFA Champions League group stage game. "He's one of the best players, and he shows that with his stats."