There is a gap that separates the team that is superior in this competition, and the team that will be eliminated in the round of 16 later. we can compare it with the depth of players they have, consistency, teamwork, mental readiness, then combine them into a team that is more prepared and established as a candidate to win this competition trophy.
and yes all the teams that enter the last 16 of the champions league, have the same one formula. the formula is, win the fight in each match after match. Chelsea is no exception, even though this team does not have a high probability of continuing to advance to the Champions League final later. even so, Potter will prepare his troops to face Dortmund in the round of 16 match later. I'm optimistic, at least Chelsea will advance to the next round after overthrowing Dortmund. however, when compared to Manchester City. clearly, there is a gap that distinguishes that Pep Guardiola's army is more prepared and established when compared to Chelsea.
It's clear that we are not going to see players being that different as a group, but super different individually and that makes the difference. When you take for example Bruna Silva and put him in Benfica, then Benfica doesn't suddenly become a UCL title contender, or when you put Haaland on Dortmund or something they weren't, and that's how you know that these players are not individually winning anything, but when you put them together suddenly they are much better.
So, you may see Haaland as a great talent, but he means nothing by himself, only the context of the team makes him so much better and have a chance to win in the long run. That's the difference between lower and higher level teams.
Well, each player has a role, in an interview with a very good player who had Brazil, I don't know if you remember him, I was small but I really liked how Bebeto and Romario did at that time, Romario said something that is very decisive , that his Brazilian team at that time played for him, for him to be the scorer, to be the player who stood out the most, and for the team's prize was the Victories they could savor, he made the selfishness of some of his teammates outside, as long as Brazil always won, he was very intelligent, because if a team plays in favor of a player shining because he is very good, and his reward is always winning, it is a good deal, I think that until a team comes back and return to that thought they are likely to win a lot.
Here opinion on the most famous players:
JJohn Stones compares playing alongside Erling Haaland & Harry Kane 
John Stones has compared playing alongside Erling Haaland for Manchester City with playing with Harry Kane for England and insisted he would not swap the England captain for City's star man.
The 28-year-old defender is one of a select group of players to have played alongside both Haaland and Kane, two players who can make a worthy claim for being the best striker in world football.
Source:
https://www.90min.com/posts/john-stones-compares-playing-alongside-erling-haaland-harry-kane