Reports indicate that Rodri is expected to be out for the remainder of the season due to a knee injury sustained during Sunday's Premier League match against Arsenal, which ended in a 2-2 draw.
The Spaniard was writhing in pain after falling to the floor in the build-up to a Manchester City corner in the first half of the Etihad Stadium stalemate.
Rodri was able to hobble off the pitch without a stretcher but initial tests suggested he had suffered an anterior cruciate ligament injury.
The 28-year-old, who has arguably been the best player in the Premier League over the last five seasons, returned to Spain after the injury to see a specialist.
Speaking ahead of City’s Carabao Cup clash against Watford on Tuesday night, Guardiola said the club were still unsure over the severity of the injury but confirmed he would be out ‘for a little while’.
‘We are still waiting for the decision of the doctors [to see] exactly what he has,’ said Guardiola, who looks set to be without Rodri as he attempts to win a record-extending fifth Premier League title.
‘When we know it, the club or myself will announce it. He will be out for a little while.’
Rodri’s absence is expected to have a significant impact on the Premier League title race, with Arsenal and Liverpool appearing to be Man City’s biggest rivals again this season.
Asked what Rodri’s injury means for the title tussle, Arsenal hero Paul Merson told : ‘I think it’s major.
‘For all the top, top drawer players Man City have got, Rodri is world-class. He gets into every other football team in the world.
‘There’s not many who can say that and he is one of them. He will be sorely missed because he’s an exceptional player who knits it all together.’
After facing Championship side Watford in the cup, Manchester City resume their Premier League campaign with a tricky trip to St James’ Park to take on Newcastle United.
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