Transfer Wrap: Eredivisie
Ajax's Toby Alderweireld joined Atletico Madrid while several other clubs were busy before the Eredivisie transfer window shut on Monday.
The departure of Alderweireld was the headline news, with the exit of the defender sure to be a blow to defending champions Ajax.
Ajax – who have won the last three Eredivisie titles – have now lost two stars in the last week, with Alderweireld joining Tottenham's Christian Eriksen in leaving the Dutch capital.
The Belgium international was linked with a host of English clubs, including Liverpool, Everton, Tottenham and Newcastle United, but has chosen to move to Spain to further his career.
Ajax did add to their squad, though, signing 23-year-old midfielder Lerin Duarte from Heracles for an undisclosed fee.
Duarte has signed a four-year deal and was compared to Edgar Davids by Ajax technical director Marc Overmars after joining the club.
Heracles kept busy, signing Morocco midfielder Iliass Bel Hassani from Sparta Rotterdam, and experienced German midfielder Simon Cziommer joined on a free transfer.
Heerenveen striker Mark Uth also joined Heracles, on loan for the season.
NEC Nijmegen were also active, bringing in three players, including Manchester United defender Marnick Vermijl.
Vermijl has signed on loan for a season, while Red Bull Salzburg midfielder Jakob Jantscher signed a permanent deal.
Jantscher, 24, was on loan at Dinamo Moscow last term and has enjoyed a good career in Austria, while the club's other inclusion saw Samuel Stefanik arrive from Trencin.
Vitesse also dipped into the loan market, bolstering their ranks with the loan arrivals of Chelsea's Sam Hutchinson and Everton's Francisco Junior, both on season-long deals.
Hutchinson is the sixth arrival from Chelsea, with Vitesse hoping their partnership with the UEFA Europa League champions can bear fruit.
Gael Kakuta, Patrick van Aanholt, Christian Atsu, Lucas Piazon and Cristian Cuevas have already joined Vitesse from Chelsea on loan.
Francisco Junior, 21, arrived at Everton in 2012 from Benfica but failed to break into the first team, making just one appearance.
PEC Zwolle signed midfielder Leroy Labylle from MVV Maastricht, who signed a three-year contract, while Feyenoord loaned out defenders Matthew Steenvoorden and Lucas Woudenberg to Excelsior.
FC Twente moved Joshua John out of the club, as he joined FC Nordsjaelland on a permanent move, while Heerenveen midfielder Sven Kums left to join Zulte-Waregem of Belgium.
Kums was immediately replaced by 21-year-old Ajax midfielder Joeri de Kamps, who signed a loan deal for the rest of the season.
Nigerian Uche Nwofor joined Heerenveen on loan for the season, from VVV Venlo, Roland Alberg signed a one-year deal at ADO Den Haag from Elazigspor and Robert van Boxel joined Cambuur on loan from Sparta Rotterdam.