Dortmund lost the game to Leipzig but it was not just because of the good performance we saw in Leipzig but I think Dortmund was making many mistakes in this game and to be honest, after all these mistakes they had during this team, Leipzig won the game was not surprising at all. For example, Ramy Bensebaini the defender of Dround scored a weird own goal in this match.
It was quite unfortunate that the two Bundesliga champion has the worst performance ever which is Borussia Dortmund and Bayern Munich, they both lose to a smaller teams they can easily win, actually I don't know if you observed something on today's match because almost all the big teams here and other leagues has a difficulty wining there matches today. But however of all the matches they have played today, Bayern Munich match was actually what kept me thinking if Bayern Munich deliberately allow Frankfurt to win them or it was there inability to perform well that made them conceive that much.
Inasmuch as I know, you can Call Frankfurt a small club but you see Leipzig don't call them small club because Leipzig is a big competitor in the bundesliga like they competites with bigger clubs in the German bundesliga and won so their winning Borussia Dortmund isn't a surprise at all regardless of the fact that Borussia Dortmund had a red card.
For Bayern Munich, their loss to Frankfurt will cause them a lot in their title race should Bayern Leverkusen win Stuttgart in their match today.