Nathan Ake, Sergio Gomez and Matheus Nunes all start against the Serbians, who are also known as FK Crvena zvezda, after coming off the bench during the win at West Ham. They replace Manuel Akanji, Josko Gvardiol and Jeremy Doku, who all drop to the bench.
Stones has been out since the Community Shield, Grealish suffered a knock prior to the recent international break and Kovacic suffered a problem while away with Croatia this month.
Guardiola said at a press conference on Monday: "They are getting better, not for tomorrow. [Kovacic and Grealish can play] hopefully [against] Nottingham [Forest] or the next games.
“We need them soon, we need Jack to compete with Jeremy [Doku], the feeling to play has to be good to be in the squad.”
Subs: Ortega Moreno, Carson, Phillips, Doku, Gvardiol, Akanji, Bobb, Lewis
Injured: Stones, Grealish, Kovacic, De Bruyne
Time and date: 8pm, Tuesday September 19, 2023
Venue: Etihad Stadium