Hasan Gökhan Sas (Turkish pronunciation: [hasan ?a?], born 1 August 1976) is a Turkish football coach and former international footballer, who is currently the co-assistant manager of Galatasaray, alongside co-assistant manager Ümit Davala and manager Fatih Terim.
He is best known for his time at Galatasaray and for his performance with the Turkey national team at the FIFA World Cup 2002, where he was voted into the All-Star Team.
During both assignments, he played as a winger with great success.