Yea, City defense is weak and they need to strengthen it, if they want to improve their performance to the best. The players are old and getting weak which is affecting their performance. It's very disheartening that City is be 20 points away from the top of the table. I hope that City will be able to finish on top four this season in order for them to qualify for UCL next season.
Man City must maximize the opportunity to continue to secure the top 4 position in the standings. If not, they must forget about avenging their defeat in the Champions League.
Given the current standings, the competition for 4th or 3rd position will be quite tight considering several teams have a small point difference. Nottingham is not impossible to be shifted by Man City from their current position. The difference is only 3 points and Nottingham's performance has also not been good in several matches. I think Man City's chance to finish in the top 4 of the Premier League standings is quite big.