Their first European match for 25 years according to my Koln-supporting chum who wanted me to get him a ticket. I found him a ticket but he had to drive here from Germany on the day and back the same night so I talked him out of it for the sake of his three-week old daughter.
He will start with a mixture of bench and squad players, maybe use a couple of guys like Kolasinac or Bellerin who don't need much rest and have the likes of Sanchez on the bench in case they are needed.
Losing this game wouldn't kill our chances of going through but losing at Chelsea (which will probably happen anyway seeing as they have the easiest of games at home in the CL) will leave us uncomfortably close to the relegation zone with more than an eighth of the games played.