Midfielder Rodri suffered a hamstring injury in Tuesday’s Champions League clash with Atalanta and will be out for around a month.
Left-back Zinchenko has undergone minor surgery on a knee problem and could be unavailable for up to six weeks.
The loss of Rodri for a spell that includes City’s much-anticipated top-of-the-table Premier League clash with Liverpool on 10 November is a major blow.
The Spaniard had been playing in defence due to injuries to centre-backs and, although John Stones and Nicolas Otamendi are now available again, the news limits Guardiola’s options.
Speaking at a press conference, Guardiola said: “They told me after the international break he will be ready again.”
Midfielder-turned-defender Zinchenko missed the Atalanta clash and has since had an operation.
Guardiola said: “He had a contact with the knee and felt something in the bone. He’s had to stop for four or five weeks.
“He’s had some surgery to clean up the knee. It’s not a big issue but he’ll be out for five or six weeks.”
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