The 19-year-old Heerkens has signed a five-year contract in Amsterdam, where he's expected to become the first goalkeeper in the coming seasons.
"We are pleased that Joeri Heerkens has chosen Ajax," Ajax director Alex Kroes said on the club website.
"Joeri is a talented young goalkeeper with all the qualities needed for the position: height, reflexes, composure, focus, and the right mentality. He shows commitment and an enormous drive to improve. We believe he can develop very well at Ajax and are confident that, in time, he can grow into the role of first-choice goalkeeper.”
Heerkens confirmed his departure from Sparta Prague and the Czech Republic on Instagram earlier on Monday.
"The country where I was born with a mission, the country where I set my first steps onto the football field, the first steps towards my dream," Heerkens wrote. "I will always be grateful that you taught me the hard way. You created a person that is ready to conquer the world, you created a person that is ready to fulfil his dreams."
The Czech-born Dutch youth international joined Sparta Prague in 2021 after playing for TJ Slovan Broumov, FK Nachod, and FC Hradec Kralove earlier in his youth career. The 19-year-old goalkeeper has not made his professional debut for Sparta Prague, despite being called up to the matchday squad in the final weeks of the 2024/25 Chance Liga season.
European champion
Heerkens represented the Czech Republic at the youth level until 2023, when he switched to the Netherlands and joined their U18 squad. Last summer, Heerkens played every minute of the Under-19 European Championships, which he won with the Netherlands after beating Spain 1-0 in the final.
