Phil Anderton, the chief executive of Al Jazira, has left his role with the Pro League champions.
Circumstances surrounding his departure are unclear but Anderton is understood to have resigned last week, citing personal reasons and he left the UAE on Friday.
Steve Hall, the commercial and marketing manager, recruited from Manchester United, and the club's facilities director have also left the Abu Dhabi club.
Anderton's surprise move leaves Sheikh Mansour bin Zayed, the chairman of Al Jazira and owner of Manchester City, looking to fill the chief executive role at both his clubs following Garry Cook's resignation.
Cook conceded he made an "error of judgement" in mistakenly sending an offensive email to the mother of Nedum Onuoha, the City defender, which prompted an internal investigation led by Khaldoon Al Mubarak, the City chairman.
The email - intended for City's football administrator Brian Marwood - appeared to mock Onuoha's mother, who was suffering from cancer.
Anderton took up his role at the Mohammed bin Zayed Stadium in January 2010.