Playing in Ankara's Eryaman stadium, Galatasaray's Halil Dervisoglu fired a classy long-shot to break the deadlock in the 44th minute. The Istanbul football club doubled the gap when Emre Akbaba made a close-range finish in minute 53.
Galatasaray made it 3-0 in minute 65 but the goal was ruled out after a Video Assistant Referee (VAR) review.
Akbaba was the scorer but before his goal, Dutch striker Ryan Babel, who assisted him, was found to have touched the ball with his arm.
With this victory, the second-place Galatasaray increased their points to 75 after 37 games.
Having 81 points, Besiktas edged closer to the Super Lig title with a victory against Atakas Hatayspor on Saturday, while Fenerbahce collected 73 points with a game in hand.
Week 39 results & fixtures:
Besiktas - Atakas Hatayspor : 7-0
Yukatel Denizlispor - Caykur Rizespor: 0-1
Ittifak Holding Konyaspor - Fatih Karagumruk: 5-1
Fraport TAV Antalyaspor - Goztepe: 2-3
Genclerbirligi - Galatasaray: 2-0
Medipol Basaksehir - MKE Ankaragucu
Helenex Yeni Malatyaspor - Hes Kablo Kayserispor
Kasımpasa - Aytemiz Alanyaspor
Fenerbahce - B.B Erzurumspor
Gaziantep - Demir Grup Sivasspor</p>