Edwin van der Sar has compared Matthijs de Ligt to Cristiano Ronaldo, claiming they share a similar mentality to be among the world's best.
Van der Sar played a pivotal part in developing Erik ten Hag's team in his role as Ajax CEO, with prospects such as Frenkie de Jong and Donny van de Beek graduating through the club's famous youth system.
Netherlands international De Ligt has turned in some indifferent performances since moving to Turin and was at fault for Northern Ireland's goal against the Oranje in a Euro 2020 qualifier on Thursday, but Van der Sar has no concerns over the defender's ability to adapt.
"He had been at Ajax all his life," Van der Sar told ESPN. "So to step away, move with your girlfriend and the family to a different city in Italy, he must learn a new language and get to know his team-mates.
"His mentality, that of someone who always tries to improve, makes him want to be the best defender in the world. And I've seen that with a few players, one of them is playing for his team, Cristiano Ronaldo.
"He has the same desire and hunger as De Ligt. Matthijs is only [20 years old]. He was fantastic for us at Ajax, our rock and our captain."
Despite De Ligt's error, Netherlands went on to beat Northern Ireland 3-1 to move top of Group C, as a Memphis Depay brace and a goal from Luuk de Jong earned the Oranje a late win.
Their Euro 2020 qualifying campaign continues on Sunday as the Nations League runners-up travel to Belarus.