On the back of a solid pre-season, Pep Guardiola hinted that Douglas Luiz would play as a back-up for Fernandinho, 33, due to the club's failure to bring in another defensive midfielder in this summer's transfer window.
However, the 20-year-old Brazilian was denied a work permit by the Home Office despite backing from both the Premier League side and Brazilian national side manager Tite.
The enigmatic Pep Guardiola was understandably disappointed with the decision. The Home Office insist that "only the most talented non-EU players meet new criteria" and the Catalan responded, saying "I accept the rules but it's difficult to understand. They don't know him.
"They have to judge if he has the ability to decide. Me and [Brazil manager] Tite know more about it. They don't know him, not one game or training session. We spent £12-£14m because he's a player with a huge capacity to play with us."
Douglas Luiz spent last season on loan at Girona albeit only making 17 appearances, and is now linked with a move to Portuguese side Benfica.
City have said they will consider offers for the Brazilian.