It seems that these 3 teams suffered defeat due to the impact of the upcoming UCL match schedule so that some players did not perform optimally. We can see from the statistics in the following picture.


Statistics Frankfurt vs Union Berlin

It is clear that Frankfurt actually has a great chance to score and even can hold the match to a draw. Unfortunately, Frankfurt players must appear to maintain their physicality so as not to force themselves to score a winning score and sacrifice their physicality. But actually this is dangerous for their current position which can provide an opportunity for Freiburg to shift Frankfurt's position.