Former Feyenoord captain Steven Berghuis received 19 pages worth of serious threats, including taunts wishing death upon him and his family.
Last month, the Netherlands international made the move from Feyenoord to Ajax in of the most controversial transfers in the history of Dutch football.
Only a select few players have played on both sides of the 'Der Klassiker' derby in the Eredivisie and already there's been mass hostility from Feyenoord supporters.
Immediately after the €4 million deal was confirmed, fans began burning his shirt after feeling betrayed by his decision.
But that has escalated to sickening levels, with Berghuis going to the police to press charges in relation to the many abusive messages he was subjected to.
Berghuis could line up for Ajax vs Feyenoord on his 30th birthday on 19 December and many of the threats involve fans stating what will happen to him on that date.
As per De Telegraaf, Berghuis, who sent a letter to police, was told he would have fireworks released on his face and that he would die on his birthday.
Fans from the Rotterdam club also boasted about knowing where he lives.
Ajax chief executive Edwin van der Sar said a "boundary has been crossed" in regards to the threats.
Feyenoord also condemned a banner that emerged on social media where fans referenced the death of crime journalist Peter R. de Vries, who was shot in Amsterdam last month.
Berghuis, who also played for Watford, scored 87 goals and made 64 assists in 199 games for Feyenoord, playing a crucial role in the club's first league title win for 16 years.
The 29-year-old said competing for trophies and playing in the Champions League were key factors as to why he joined Ajax.
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