Ole Gunnar Solskjaer's Besiktas beat Fenerbahce 1-0 in the Istanbul derby to further dent Jose Mourinho's chances of winning the Turkish Süper Lig.
Gedson Fernandes, who flopped at Tottenham Hotspur when Mourinho was in charge, missed a penalty but then scored the only goal to hand Solskjaer bragging rights at Sukru Saracoglu Stadium.
The win sees Solskjaer became the first foreign Besiktas coach to claim an away win at Fenerbahce in 22 years and spells the end of Fenerbahce's title hopes, with Mourinho's side eight points behind leaders Galatasaray.
The former Manchester United managers, who together spent five years at Old Trafford, clashed during their time in England and faced each other for the first time since moving to Turkey.