Ajax have left captain Matthijs de Ligt out of their squad for a training camp in Austria as the player is "awaiting a possible transfer".
The Dutch centre-back has been linked with a move and Barcelona, Juventus, Manchester United and Paris St-Germain all named as potential destinations.
De Ligt, 19, led Ajax to the Eredivisie title, the Dutch Cup and Champions League semi-finals last season.
He joined the club aged nine and has scored 13 goals in 117 games.
Source: BBC Sport