Bringing new players that will add value to the squad is very important because it is obvious that the team lack something in the squad which is the main reason for all these poor performances.
Remember, Manchester City was doing well before Rodri get injured, but they started to flop when he is injured, and Kevin De Bruyne also got injured then which was the reason they had poor performances in the back, but when KDB is back from injury, we were expecting some improvements in the squad, but they keep losing games which shows that their main problem defense.
If they can sign good defenders and defensive midfielder in the January transfer window, then they can get it right.
I doubt with Manchester City performance at domestic league will have opportunity qualify to knock out round in Champion League behind two matches left have to face PSG and Club Brugge. Have win for two matches left if Manchester City won't dropped from playoff round spot standings and have opportunity get qualify to knock out round by playing at playoff round match.
Since leaving by Rodri after getting injury, Manchester City have difficulty keep in the winning trend and their performance not only poor at UEFA Champion League but also have dropped to 7th standings place in Premier League have 12 points left from Liverpool. Crucial position for Manchester City in this season after Champion League adopting new format, only won 2 of 6 matches become bad record for manchester city their appearances in champion league.