Before we get started: None of this is going to matter when Manchester City face Slovan Bratislava, who lost their opening UEFA Champions League match to Celtic 5-1. It likely won't be a problem against Fulham because that match is at home, and it probably won't matter away to Wolves, who have earned six total points in the Premier League since the end of March.
Sparta Prague at the Etihad? Should be fine. Southampton at the Etihad? Should be a blowout too. So, even though it already seems like Man City can't withstand the loss of Rodri, their world-class midfielder and arguably the best soccer player on the planet, after the 1-1 draw with Newcastle on Saturday, we could very easily find ourselves flipping the calendar from October to November and wondering what all the fuss was about.
City should cruise in the Champions League, and they might have nine points from nine in the Premier League over the next month. In fact, that is the most likely outcome. But almost every big club can face the loss of any star player for a short period of time. City expect to play somewhere around 60 matches this season -- something Rodri himself was sounding the alarm on right before his knee gave out against Arsenal. That means City have about 50 more games to play this year without the best midfielder in the world.
Will they be fine? Are they doomed? Can Pep Guardiola lock himself in a dark room for multiple days and come out with some magical solutions? Your answers to those questions say a lot about how you think soccer works.