Ajax Amsterdam coach Erik ten Hag has said that the club will have to change their playing style after the sale of Hakim Ziyech to Chelsea.
The Dutch champions began their preseason training amid reports that up to six players could leave before the new season in the Netherlands starts.
“If you lose players who have had a big influence on the game, the playing style will change,” ten Hag told Dutch NOS television on Sunday.
“You lack specific qualities. But of course, the intentions remain the same. You should always set the bar higher than last season. The challenge is to get even more out of the players who are there now."
Ziyech was the star as during Ajax's brilliant Champions League run last season when they reached the semi-finals. But success for the club has meant their players have been in high demand.
The club last season sold Frenkie de Jong to Barcelona and Matthijs de Ligt to Juventus while Joel Veltman has gone to Brighton and Sven Botman joined Lille.
It is expected that Andre Onana, Nicolas Tagliafico and Donny van de Beek could also still leave before the new season gets underway next month.