Netherlands coach and former Barcelona star spoke to the Catalunya Radio about Frenkie de Jong and Matthij de Ligt.
"De Ligt and De Jong are special for several reasons. De Ligt is young, 19 years old, and already plays in an important position as a central defender. He is Ajax' captain and he is from the Ajax school and that's like saying he's from Barca school because it means he has a lot of technical and tactical quality. He will be the best centre-back in the world in two years," he said. "De Jong is 21 years old and can play in both positions, either as a pivot or as an outside midfielder in a three-man midfield. He can and must still improve in many things looking up, like the last pass, assists and shooting from outside the area," Koeman added.
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