Fenerbahce suffered a shock 2-1 defeat against Alanyaspor at the Sukru Saracoglu stadium on Sunday.
The Yellow Canaries were coming off the back of a loss to rivals Trabzonspor.
The Istanbul giants had a turbulent week after publicly criticising the referee in the Trabzonspor game.
The Yellow-Navy Blues did not get off to a great start against Alanyaspor.
In fact, it was Emre Akbaba who opened the scoring for the visitors on 75 minutes.
Serdar Dursun did equalise five minutes later but it was Alanyaspor who had the last laugh from Efkan Bekiroglu scored the winner in the second minute of additional time.
The defeat saw Fenerbahce drop into 4th place on 19 points while Alanyaspor moved into 3rd position on 20 points.
In the other major game over the weekend Trabzonspor won their third game in a row beating Goztepe 1-0 away from home with Gervinho scoring the winning goal on 56 minutes.
The victory moved the Black Sea based side moved four points clear of Hatayspor at the top of the Super Lig table.
The final game of the week is set to be a blockbuster affair between Galatasaray and Besiktas. With both sides tied on 17 points a win will take them above Fenerbahce.