Grégory Sertic (Croatian: Sertić; born 5 August 1989) is a French professional footballer who plays as a defensive midfielder for Swiss club FC Zürich on loan from Olympique de Marseille.
Born in Brétigny-sur-Orge, Essonne of Croatian descent, Sertic joined FC Girondins de Bordeaux's youth system at the age of 15, from the famed Clairefontaine academy. During the 2007–08 season, spent in the Championnat de France Amateur with the senior reserves, he earned praise from first team manager Laurent Blanc.
Sertic made his debut in Ligue 1 on 29 April 2009, starting in a 2–3 away win against Stade Rennais FC. His maiden competitive appearance had taken place on 11 November of the previous year, in the 4–2 home victory over En Avant de Guingamp for the round of 16 of the Coupe de la Ligue where he came on as a late substitute; his first goal in the former competition was scored in only his second appearance, helping the hosts defeat FC Sochaux-Montbéliard 3–0.