Super Lig Wrap: Fener hammer Kayserispor
Ersun Yanal's men - beaten 2-1 by Karabukspor in their previous outing - took the lead through Cristian Baroni's penalty after 52 minutes, only for Kayserispor attacker Bobo to equalise seven minutes later.
The hosts' advantage was quickly restored just after the hour mark thanks to striker Moussa Sow, before Mehmet Topal, Emmanuel Emenike and Caner Erkin rounded off the win.
Galatasaray remain eight points behind their fierce rivals following their 3-1 win at bottom side Kayseri Erciyesspor, Wesley Sneijder, Burak Yilmaz and Felipe Melo all finding the net in a comfortable win for Roberto Mancini's side.
However, there were defeats for third-placed Kasimpasa and fourth-placed Besiktas, who both suffered setbacks in their quest for UEFA Champions League football.
Kasimpasa slipped to a 4-2 home loss to Akhisar Belediyespor, despite a double from Adem Buyuk, while Ermin Zec's first-half strike condemned Besiktas to a 1-0 defeat at Genclerbirligi.
Defender Manuel da Costa netted twice in Sivasspor's 3-1 triumph over Karabukspor on Sunday, and earlier in the round relegation-threatened Elazigspor overcame Rizespor 1-0 thanks to a second-half goal from Serdar Ozkan.
Eskisehirspor suffered their first defeat in five league games as they succumbed to a surprising 4-1 loss at Konyaspor.
An Erdal Kilicaslan double and an injury-time strike from Recep Aydin made sure of the points for Konyaspor after Eskisehirspor's Henri Bienvenu had cancelled out Tomas Borek's first-half opener.
Elsewhere, Trabzonspor beat Antalyaspor 2-1 and Gaziantepspor drew 0-0 with Bursaspor.