Besiktas suffered a shock defeat away to Hatayspor in the Super Lig on Monday.
The Black Eagles headed into the game having won one of their previous five games.
The visitors did get into a great start when Wout Weghorst scored in the first minute but Ze Luis equalised in the second half and Kaan Kanak scored a last gasp winner to send Besiktas back to Istanbul without a point.
Despite the defeat Besiktas are still only four points behind league leaders Fenerbahce but have played an additional game.
The defeat resulted in rumours in the Turkish press that head coach Valerian Ismael’s job could be in danger.
Besiktas moved quickly to defend their manager but the Istanbul giants will have to improve results to silence the critics.
The Black-Whites face Umraniyespor next at the Vodafone Park stadium followed by a major test in Istanbul derby against Galatasaray at the Ali Sami Yen.