Crystal Palace have signed Netherlands defender Jairo Riedewald from Ajax on a five-year deal for an undisclosed fee.
Riedewald, 20, previously played for new Palace manager Frank de Boer at the Dutch side, making his first-team debut under him in 2013.
He made 93 appearances and was part of the 2014 Eredivisie title-winning side.
Riedewald is Palace's second signing of the transfer window after Chelsea midfielder Ruben Loftus-Cheek joined on a season-long loan deal.
"It is a great opportunity to be working under De Boer once again," Riedewald, who has three caps for the Netherlands, told the Premier League club's website.
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