Coach Maurice Steijn has left Ajax by mutual consent after four months in charge.
The 49-year-old joined from Sparta Rotterdam in June on a three-year deal.
But a poor start to the season has left the 36-time Dutch champions second bottom of the Eredivisie table with just one win from seven league games.
Steijn and Ajax's management agreed to part ways after meeting twice on Monday, with assistant coach Hedwiges Maduro taking over as caretaker boss.
Ajax won just two of their 11 games in all competitions under Steijn, who has also managed ADO Den Haag, VVV-Venlo and NAC Breda.
Chief executive Jan van Halst said: "We have worked together very intensively and professionally in recent months, but the sporting results and the development of the team lagged behind.
"That is why we sat around the table again. Maurice now also indicated he had doubts whether he is still the right man in the right place."
Erik ten Hag led Ajax to three straight league titles before leaving for Manchester United in the summer of 2022 and his replacement Alfred Schreuder was sacked in January 2023.
Interim boss John Heitinga was given the job until the end of last season, when Ajax finished third, before joining West Ham United as a first-team coach.
"It is a terrible shame," Steijn added. "Everyone knows that I have done everything I can to bring Ajax back to where this club belongs, but I was not successful."
