Ajax have not found a way past Czech opponents FK Baumit Jablonec in the first 45 minutes of their Europa League qualifying knockout round first-leg encounter.
Riechedly Bazoer's 17th-minute strike, which went just outside the Jablonec post, was the Dutch side's first chance of the game.
Davy Klaassen's cross then found Arkadiusz Milik, the forward unable to keep his header on target.
Jablonec responded through Jan Gregus, who put a curling effort just wide after 32 minutes.
Anwar El Ghazi's 39th-minute effort was too weak to beat Jablonec keeper Michal Spit, with the tie remaining scoreless at the half-time whistle.