Istanbul giant and current Turkish Süper Lig leader Beşiktaş was stunned by minnows Kasımpaşa in a 1-0 defeat Sunday.

In the match of two unevenly matched sides, Beşiktaş looked the more likely to score. Despite keeping most of the possession, the Black Eagles lacked cutting edge up-front as their main forward Vincent Aboubakar was out due to injury.

Host Kasımpaşa picked up one of the few chances that fell their way early on. It eventually claimed the victory thanks to a classy goal by Aytaç Kara from outside the penalty box in the 19th minute.

However, it could have gone ahead in the 56th minute but Beşiktaş goalkeeper Ersin Destanoğlu denied Kasımpaşa’s Swedish forward Isaac Thelin from the spot at Istanbul's Recep Tayyip Erdoğan Stadium.

With the win, Kasımpaşa jumped to 14th place with 34 points while Beşiktaş remained top of the league standings with 64.

In the other matches on Sunday, the second-last team in the league Erzurumspor lost 2-1 to Konyaspor, while relegation-threatened Ankaragücü picked up a key 1-0 win against Antalyaspor.

Current champion Başakşehir looked to be back in rhythm as it picked up a 3-1 win over Yeni Malatyaspor.

Fifth-placed Alanyaspor, in the meantime, suffered a shock 2-1 defeat against 19th-placed Gençlerbirliği.