This comes after Amakhosi were beaten to the 2019/20 PSL title by their Gauteng rivals Mamelodi Sundowns last weekend.
Chiefs had led the league standings for the better part of the season and at some point, they were 13 points above their closest rivals, Sundowns.
Reports indicating that Middendorp was set to be fired by the Naturena-based club emerged following Amakhosi's draw 1-1 with Baroka FC on Saturday which was the final day of the season.
The Soweto giants released the following statement on Wednesday afternoon indicating that Middendorp's two-and-a-half-year contract which he signed in December 2018 had been terminated.
"After reviews conducted by Kaizer Chiefs Chairman Kaizer Motaung and the club’s management, Amakhosi have decided to part ways with coach Ernst Middendorp with immediate effect," a club statement read.
Motaung explained the process that led to the decision to part ways with Middendorp.
“We deliberated and considered many aspects related to the team, including our way of playing, our performances and the results before coming to the decision,” said Motaung.
“We truly believed and hoped that our 50th anniversary year would be better, and it indeed looked promising. The decision taken is part of a strategy to have the team win trophies again and to make our supporters happy because they deserve better.”
Amakhosi struggled in the bio-bubble under-Middendorp as they registered just one win out of six matches and the experienced tactician was under immense pressure.
“After giving the coach and the technical team the ammunition required to compete in the new season. There were some improvements, and this was evident during the first seven months of this 2019/2020 season," Motaung added.
“However, when the league restarted post-lockdown, things changed, and we looked a totally different side in our last eight league matches.
"We witnessed some heart-stopping performances and we were overtaken on the log in the last game of the season, which truly broke our hearts. We have to take responsibility – we can’t wait and allow this situation to continue.”
Motaung went on to thank the former Arminia Bielefield manager for his efforts and work: “We wish him all the best for the future.
“We pride ourselves on having built a strong legacy and a culture based on winning.
“We are aware that the supporters are hurting, and the outcry is too loud to ignore. It is important for our loyal supporters to know that we feel their pain.
"We are a listening organisation and we respect their right to express their dissatisfaction with the team’s overall performance," he explained.
“While we are wounded, we need to remember that the key principle of loyalty is showing unity and standing together in solidarity when the going gets tough.”
The veteran football administrator concluded by stating that a new coach will be announced before the team resumes pre-season training ahead of the 2020/21 season.
“We will announce the new coach before the team returns for pre-season training,” Motaung concluded.