Never try to underestimate your opponent. Did you even forget when third tier club has beaten bayern at DFB pokal? Bayern must have gained a great deal of knowledge and insights from the outcome of that particular match. Bayern can start to think about how to beat the weak club by using the best performance. It doesn't even matter what clubs faced by bayern. Many people and I were quite surprised by the result of Bayern being knocked out of the DFB pokal by a team from a lower tier. If you were watching that match and you shall know if you will never try to underestimate your opponent. Being kicked by low tier team is even hurting rather than a rival in the bundesliga. It's caused by many people will be starting to mocking you.
They will also being so disappointed with your club. Remember this.
You are right, that actually the weakest opponent can be a stumbling block for a big team. and that's why football is unique, sometimes the results are far from our expectations. but we also have to look at it from the other side, when Bayern lost in DBF Fokal against a 3rd division team. Actually the reason was very classic, the poor performance of several Bayern players and Tuchel not playing his core squad. even Kane, was not involved at all. Choupo-Moting as a center forward, Mathys Tel was placed on the wing, Muller was an attacking midfielder, Sane played poorly. Frans Krastzig is a 20 year old player who is being tested by Tuchel as a pivot, De Ligt is injured, Bouna Sarr is a 30 year old second tier player. and the bad thing is, Neuer played badly.
But, even so, Bayern should have been able to win the match. because after all, overall these two teams are on different levels. Even though Bayern actually controlled the game, in fact they lost. and, that's football in all its uniqueness.
Talking about the Koln versus Bayern match, on paper Bayern Munich is far superior and has a very high probability of winning the match between these two teams. Moreover, referring to Koln's ranking which is in second place in the relegation zone. Meanwhile, Bayern, ranked second in the top four of the Bundesliga, has a clear gap. In this match, Thuchel will play his full squad and getting 3 points is the result they must get. but, once again. Football is unique, we'll see how this match goes.