The midfielder's knee injury has coincided with City's stunning form collapse, which has seen Guardiola experience the worst run of games in his managerial career.
He said on Friday: "We have known from the beginning, the only problem is Rodri's absence due to injury. We are playing the season without our best player and winner of the Ballon d'Or, and without the best player of the Premier League 2023/24, Phil Foden. He has played 4-5 games but is not in his best moment.
"How can a team play without centers, without the Ballon d'Or and without the best player of the last Premier League for the whole season? It's difficult: the Chicago Bulls won six rings with Michael Jordan, after his retirement how much did they win?
"We have problems, when they come back we will be strong again, a good team."
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