Timm Klose and Alex Tettey will miss Norwich City's game with Birmingham City on Friday night (7.45pm) through injury.
Klose has been nursing a knee problem over the past few weeks and he has flown to Switzerland to see a specialist about the issue.
Speaking at his pre-match press conference, Daniel Farke said that Klose will miss the next two games and, if he requires surgery, he could be sidelined for the next six weeks.
Meanwhile, Tettey had a scan on an adductor injury after the West Bromwich Albion game and it revealed a muscle strain, which rules him out of action for the next three weeks.
Farke also revealed that Moritz Leitner's absence may go on a bit longer and he may not return to training until the end of January.
However, Farke delivered positive news on the fitness of Marco Stiepermann, Jamal Lewis and Emi Buendia.
"Marco Stiepermann has trained all of this week. He is available tomorrow but we will make a late decision as to whether he will start.
"He had a brilliant December and was crucial for us. We have missed to it's great to have him back available.
"It was important for Jamal Lewis and Emi Buendia to have the game at West Brom. Emi played 70 minutes, Jamal with 75. They are now back in shape and fully fit."
Farke also confirmed that Grant Hanley is back available after serving a one-match ban following his red card in the FA Cup defeat against Portsmouth.
Meanwhile, Ivo Pinto is back training at Colney after a proposed transfer to a club in Turkey fell through.