AMSTERDAM (AP) — The Netherlands' injury list lengthened ahead of two crucial European Championship qualifiers with midfielder Davy Klaassen and winger Quincy Promes withdrawing from the squad.

Netherlands captain Arjen Robben, who has not recovered sufficiently from a groin injury, and defenders Ron Vlaar and Stefan de Vrij already had been ruled out of the squad that was gathering Monday at a hotel on the North Sea coast to begin preparations for the final two matches of a disastrous qualifying campaign.

Klaassen suffered a concussion in Ajax's 2-1 loss to PSV Eindhoven on Sunday and will definitely miss Saturday's match against Kazakhstan in Astana. His condition will be assessed later to establish if he is fit for the final qualifier against the Czech Republic on Oct. 13 in Amsterdam.

Promes is out of both matches with a hamstring injury.

Netherlands coach Danny Blind called up Ajax midfielder Riechedly Bazoer and Feyenoord winger Eljero Elia as replacements. It was Bazoer's first call-up for the senior Netherlands team while Elia's last appearance for the national team was nearly three years ago.

The Dutch, who reached the semifinals at last year's World Cup, are fourth in Group A, battling third-place Turkey for a spot in the playoffs for next year's tournament in France. Two points behind Turkey, the Netherlands will be eliminated if the Turks win both their remaining matches.

Turkey travels to Prague to take on second-place Czech Republic on Saturday and then hosts group leader Iceland the following Tuesday. Both Iceland and the Czech Republic have already qualified for Euro 2016.