Rodri had to be substituted during City's 2-2 draw with Arsenal last Sunday, and early tests revealed that the Spain international would be sidelined for the majority of the season.
However, Guardiola has now confirmed that Rodri underwent surgery on Friday and will not make another appearance for City until next season.
‘Good surgery this morning, ACL and some meniscus things, next season he will be here. This season is over,’ Guardiola said of Rodri on Friday.
‘Unfortunately, he got the worst but it’s what it is, at that level sometimes, unfortunately, it happens.
‘We are there to support him, good recovery, step by step, and move forward.
‘What he gives us we don’t have a similar player but the other players altogether can replace what Rodri has given since he arrived to us, so we have to do it as a team and we have to find a way to play a lot of months without an important player.
‘And like all the teams want, a speedy recovery for next season to compete against them.’
De Bruyne, meanwhile, was forced off at half time in City’s goalless draw with Inter in the Champions League on September 18 and has not featured for the Premier League champions since.
When asked if De Bruyne is available to play against Newcastle, Guardiola replied: ‘No.’
Asked how long De Bruyne will be absent, Guardiola said: ‘I don’t know, before maybe the international break or after the international break, we’ll see.’
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