You sound like Manchester City will not lose to Arsenal, even though their first eleven are all injured. The Arsenal of this season is different from the Arsenal of last season, and they won against Manchester City at the Emirate Stadium this season. Arsenal is consistent and scores a lot of goals against their opponents. Arsenal is capable of beating Manchester City on Sunday.
I agree to the fact that it's very possible Arsenal may be able to beat Manchester city on Sunday but what I'm actually in doubt with is about their consistency, Arsenal's consistency is actually relative as they usually don't show the consistency with every team they get to meet, they only show with certain teams so I can say they may not actually win with a good goal margin like they have done with others but they can win.
Since Manchester city will be at home, even if a good number of their key players have been injured, they will still not be too weak to the point where Arsenal will get a land slide victory over them, the last time Arsenal won them it was just with a goal difference so I'm not expecting if Arsenal gets Lucky to beat Manchester city again if it will be such a huge one and this time around Manchester city even happens to be playing from home so they are definitely not going to be really weak and they usually have a winning mentality which makes loosing not easy for them.
Arsenal hopefully will be able to utilize the advantage that they will be getting against Manchester city and it's also an opportunity for them to once again too the league table and if they will further be able to maintain it they will definitely get to win the league this season from the defending champions Manchester city, so it will look more like they were the reason Manchester city has been unable to defend the trophy this season as they would have.