Demirel was born in Fatih, İstanbul. He joined Kartalspor as an 18-year old in 1999 and became the starting goalkeeper the following year. Demirel played in 51 matches over the next two seasons, earning a transfer to Fenerbahçe at the start of the 2002 season.
Originally backing up Rüştü Reçber and Recep Biler, Demirel made his debut for the club on 26 April 2003. After Reçber's transfer to Barcelona, Demirel competed in 19 league matches, splitting time with Biler (who played in 14 matches). He also featured in three Turkish Cup matches and won the 2003-4 Süper Lig title with Fenerbahçe.<ref... Read More