Well, if De Bruyne can't play it wouldn't change much on the side of the citizens, because pep guardiola always has a replacement. However De Bruyne plays a pivotal role on that attacking midfield, because he has the ability to distribute the ball and sometimes make a goal attempt. Pep hasn't built Manchester city on a single player, so arsenal will still have a tough game on Sunday. The tactical manoeuvre pep guardiola normally uses is to conquer the midfield and force the attack, which normally doesn't work much against arsenal because they too have players saturated at the midfield with solid defensive midfielders as well.
De bruyne not playing I'm the game against Arsenal may actually not really mean much but you can be sure that they may actually be affected and this will happen to be the second time this season that against Arsenal Manchester city played without a key player like de bruyne and it's very obvious going by the result they got in their first meeting that Manchester city needs de bruyne in this game.
Although the team is so much dependent on him alone to determine the outcome of the game but he's really going to influence the results Manchester city will be getting if he's present playing this game and that why I'm of the opinion that he's very much needed in this game and his presence will aswell have an effect on the psychology of both team been aware of his abilities a d what the team could possibly achieve with him been present in the team in that match.but regardless of all these I can be certain that it's going to be a tough one for Manchester city and Arsenal.
Manchester city wouldn't want to be beaten twice by the gunners so it very possible this game may be ending in a draw and both teams having to share their point equally by the end of the game. Manchester city for me still remains my favorite because even the victory Arsenal got over them the first time wasn't a flawless one but some how Arsenal appeared like they were lucky and they may not be this time.