It is true that the roles of Kevin De Bruyne and Haaland are very important in the squad, but Pep Guardiola knows what he has to do to overhaul his squad in this match and he has to really get used to staying focused on other players if Kevin De Bruyne and Haaland are absent because injured, so Pep Guardiola already knows which reserve players will be used. In the world of football, if you only rely on 1 or 2 players, it will not be possible to be successful in the future and of course it still requires teamwork to continue to develop well. That way, if one day one of the main players is absent, of course the other players can still make a good contribution to the squad to achieve victory.
I am also sure that Manchester City will definitely be more focused on facing their opponents in the remaining matches to achieve victory in the next match, so that they can continue to compete with Arsenal and Liverpool to win first place at the top of the standings or become champions of the English League this season.
The partnership of Kevin De Bruyne and Haaland last season was very impressive, went Haaland arrived Manchester City it was as if he's found his missing piece, playing together as teammates, but this season I noticed that Haaland performance dropped despite the fact that he's still found the back of the net multiple times, but if KDB was not injured I think Haaland goal would had been more or double the amount of goals he's score currently.
I think things are gradually becoming tough for Pep this season and needs to do everything possible to make sure they don't drop due to the absent of their key players, when De Bruyne got injured it really affected them a little but now their striker is injured, it might become difficult for them to score goals, well I trust Pep Guardiola to develop a good strategy that would sustain them from losing without Haaland, now one of the attackers have to play as a false 9, Alvarez or silva.
The decline in Haaland's performance is due to several causes and it is impossible for a quality player to have decline in performance without there being cause and I don't know what the cause is for sure, seeing Haaland and De Bruyne are already in harmony, I am very happy even though I don't know when he will appear with Manchester City, which is certain if These two players will appear again soon, of course MC will soon recover from his slump and immediately win the first position in the points table.
For Guardiola, this is not a difficulty but like a challenge that must be completed in the near future to catch up on points behind Arsenal.