Steven Berghuis has completed his controversial transfer from Feyenoord to Ajax.
The clubs reached an agreement in principle on the transfer last week, and the right winger was unveiled by his new club on Monday after all conditions were met.
Speaking about the switch last week, Berghuis said: “I am 29 years old, and it’s no secret that I wanted to take the next step.
“It is important to me to further develop myself in the sport.”
His decision has infuriated Feyenoord supporters, who are bitter rivals with their Amsterdam counterparts.
Away fans have been barred from attending De Klassieker games since 2009 due to a number of violent incidents.
Berghuis, who began his senior career at Twente, has also been linked with AZ and Watford.
He was in the final year of his contract with the Rotterdam club, but he is now under contract with Ajax until 2025.
When the Netherlands international returns to De Kuip for the Eredivisie clash between the sides on December 19, he is sure to face a hostile reception.