The Catalan giants have won all nine games they have played this season across all competitions, scoring 39 goals, more than four a game on average.
However, the visit to face Turkish champions Galatasaray in Istanbul is the first in a string of tougher fixtures for Barcelona, with Paris Saint-Germain and Real Madrid also coming up.
The Spanish champions thrashed Feyenoord 5-1 in their league phase opener but will be without Raphinha for the visit to Turkey and one of the game's most intimidating environments.
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"First of all, we have to be ready for this atmosphere," Flick told reporters Monday.
"I think this is one of the best atmospheres ever in the world. It's amazing when I hear some situations or the sounds of the stadium, what the fans are doing, it's unbelievable.
"They support their team. You also can see the results against big teams, they are playing like a big team against them, they've improved a lot."
Not since Barcelona's 2-0 win over Athletic Bilbao in LaLiga on August 27th have the Catalans been restricted to fewer than three goals.
However Flick said just one would do at Galatasaray's hostile Rams Park stadium, which has sometimes been nicknamed "Hell".
"The only thing we want is to win; this is our goal, this is what we want," said Flick.
"I'm also happy if we win just 1-0, because to see this team, how they play, how they play out (from the back), they like to play football.
"In attack they have fantastic players, so it's not easy to play against Galatasaray, especially at home."