Well it's obvious that the absence of two players Kelvin Debruyne and Rodi has contributed to their poor performance and this should let Pep Guardiola to know that the team still needs strengthening,
Yes mate I think Manchester city are suffering from extreme injury problems and the match against arsenal exposed how even them can fall without the right players, they are missing Kevin and some players are playing the wrong roles or aren't playing in their natural position.
One of the biggest mistakes they made was to sell some very important players and they didn't improve their midfield
I think what this two players are experiencing is just nature, this are players that has so much put in so much energy in the Victory of Manchester City in several seasons, I think that is why Manchester City is going through difficult times. The injury problem of Manchester City of these two players can be a serious problem of Manchester City this season in the Champions league and Premier league. Manchester City performance has reduce this season due to much energy their main players put in to win different competitions I'm last season. Let's just hope Manchester City can still revive back to their good performance.