Cologne will play for their survival in the Bundesliga without midfielder Luca Waldschmidt and defender Max Finkgräfe, the club said on Friday.
Both got injured in last weekend's match against Union Berlin and won't be available for the game against Heidenheim on Saturday.
Cologne need to defeat Heidenheim and hope for a combination of other results to avoid automatic relegation. Their only chance to stay in the top tier is qualifying for the relegation play-off against Fortuna Düsseldorf.
"We have to win our game, that's the only thing that we can influence. We've got a big push thanks to the win against Union and that is what we want to take into the game in Heidenheim," coach Timo Schultz said in a news conference on Thursday.
