We are still at the beginning of the league but Barcelona is continuing on their way with high morale. Playing without mistakes in 3 matches was an indication that Flick analyzed the team well. The main factor for Barcelona will be the El Classico matches. If they can get 6 points from Real in those matches, they will be champions this year, but if they lose 2, their chances of winning the league will be very low. They are lucky that Real Madrid got stuck with Mallorca in the first week of the league and lost 2 points.
Barcelona did amazingly at the beginning of this by winning three games and being at the top of the standings of course what their fans expect from Flick this might happen by overthrowing Real Madrid below them, but talking about El Classico we can't see at this time that Barcelona will lose with the almost equal strength that they have with their sharpness against this attack is really good and they can also lead in this next match, Real Madrid is indeed a club with a high mentality and has good significance to their game with super star players but Barcelona also has the same thing and performance that can be said to be above Real Madrid at this time, so expecting in El Clasico alone I'm not sure because at this time how Atl. Madrid and also other teams expect the same thing as them.
So in my opinion at this time for Flick and his players there is no need to think about this tough match because they still have many matches that must be completed with victory so Barcelona should focus better on small matches to take advantage of the points there and can maximize many goal opportunities so they can tear Barcelona back under Flick.