The 28-year-old was a target for Steven Gerrard but he chose to join Club Brugge instead.
Deli has revealed that Brugge had a more ambitious project and therefore he turned down the move to Glasgow.
Speaking to Nord Eclair (cited by Daily Record): “Last summer, I had three main options. Either I stayed [at Slavia Prague] with a great wage and the assurance of being captain, or I left for Rangers or Club Brugge to take up a new challenge. Club Brugge was a more attractive, more ambitious prospect for me.