Bah ruled out for six months
The 27-year-old attacking midfielder signed from Finland champions HJK Helsinki just before the transfer window closed at the end of August.
He made his debut in the 4-1 Bundesliga defeat to Bayer Leverkusen last Friday, but damaged his knee in training and underwent surgery on Wednesday.
He is expected to be out for at least the next six months. "It is bitter news for Dawda, both he and us had imagined a different start to his time here," said Augsburg's managing director Andreas Rettig.