Ferdi T, who has a history of violent crime, had told the court he considered the effigy to be funny and that he had not meant to threaten anyone.
T had hung the doll with a noose around its neck over the balcony during the match in February.
The doll’s shirt had the text Vermeer 1 on one side and NSB on the other. The NSB was the Dutch nazi party during World War II. Vermeer made a formal police complaint about the incident.
Vermeer was a member of the Ajax youth training scheme but was sold to Feyenoord by Ajax in 2014.
The racist incident also led to Ajax being fined €10,000 by the Dutch FA for not having removed the effigy as soon as it was spotted. The club earlier gave T a three-year stadium ban.