The former Madrid boss has nothing but praise for his former protege, while he also expects Neymar and Eden Hazard to shine at the World Cup.
Chelsea boss Jose Mourinho believes that Real Madrid youngster Raphael Varane is arguably the best defender in the world.
The Portuguese, who left the Santiago Bernabeu for Stamford Bridge last summer, made the French youngster a regular in his starting XI last term.
Varane earned widespread praise for his composed defensive performances and Mourinho has nothing but good memories of the center back.
Indeed, after being asked who were the young players to watch at the World Cup after being unveiled as Yahoo's global ambassador for football 2014, the Blues boss stated: "I would say [Eden] Hazard for sure, Neymar and Varane.
"I think Varane is the best central defender in the world. He is still young, but I think he's the best. Already, yes. I think he's the best defender."
Varane has made just six La Liga appearances so far this term as a knee injury kept him sidelined for the majority of the first half of the season but is expected to be named in France's squad for Brazil 2014.