Dutch giants Ajax sacked manager Marcel Keizer and assistant coach Dennis Bergkamp on Thursday, saying the club had "lost confidence in their abilities" after a string of poor performances.

"Ajax has suspended Marcel Keizer, assistant coach Hennie Spijkerman and Dennis Bergkamp and management will meet them to discuss ending their contracts," the club said in a statement.

"Management has lost confidence in their abilities to fulfil Ajax's ambitions with a string of bad performances adding to the decision," it said. 

The club also differed with former Arsenal and Dutch great Bergkamp over "the execution of its technical policy".

Ajax appointed the relatively inexperienced Keizer in June following the departure of Peter Bosz for Borussia Dortmund after a single season.

The club axed Keizer after just 174 days, the shortest spell for an Ajax coach since Kurt Linder in 1988, who got the boot after 82 days.

The Amsterdam club saw their fortunes flag over the last few months, as they failed to qualify from the preliminary rounds of either the Champions League or the Europa League.

At home, things are also not going Ajax's way and they crashed out of the Dutch Cup on Wednesday after losing on penalties to FC Twente following a 1-1 draw.

"We've had a bad summer and have been limping into the season," Ajax general manager and former Dutch international goalkeeper Edwin van der Sar said.

"Sporting-wise, the European losses were a low," added Van der Sar, who played in the 1995 final against AC Milan when Ajax won the most recent of their four European Cup titles.

He said management "has insufficient confidence" that the current side "will reach the level we expect from them" under Keizer, Spijkerman and Bergkamp. 

Reserve team coach Michael Reiziger has been appointed to lead the club on an interim basis.