Last season's treble winners won the tournament for the first time in their history as the beat Brazilian side Fluminense 4-0.
Rodri was named in the starting XI by Pep Guardiola but was unable to play out the full match.
The Spaniard was on the receiving end of a strong challenge from Alexsander, with the Fluminense midfielder booked for his tackle.
City would have been relieved to see Rodri continue with play but shortly after Phil Foden scored, fans were left concerned again.
Rodri was seen lying on the pitch in pain once again with his head in his hands after what looked to be a knee injury, a worrying sight for the Club World Cup winners.
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Guardiola opted to bring him off and replaced him with Manuel Akanji as his side saw out their comfortable 4-0 win.
Such a decision may well be precautionary from the boss as City fans will be desperately hoping it's nothing serious.
Rodri has established himself as one of the first players on their teamsheet amid a series of fine performances since signing in 2019.
He scored the winner in City's first ever Champions League triumph last season and proved key throughout their treble success.
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Much of the club's success has come down to his appearances, with Guardiola's side unbeaten in their last 47 matches when he's started.
All three of City's Premier League defeats this season have come when Rodri wasn't in the side due to suspensions.
He had plenty of action on Friday night though despite injury as they won their fifth trophy of 2023.
Julian Alvarez opened the scoring inside the first minute and netted their fourth as a Nino own-goal and Foden finish also added to the scoreline.