Kalas has sustained a hip problem, and the right-back is suspended after being shown a straight red, 20 minutes from the end at St Andrews.
Boss Slavisa Jokanovic has also made it plain he wants new signing Gohi Cyriac to challenge Chris Martin for the lone striker's role over the next few weeks.
He said: "Generally he (Cryiac) is a fast player who attacks the space, and I see him as someone as the first attacker like Chris Martin.
"I'm going to try and use him in this position, and maybe in the wide position too."
"Tomas Kalas has some hip problem - and Ryan Fredericks is suspended, so neither can play against Wigan."
Jokanovic hopes Wigan will be less of a physical challenge than found at Birmingham, where captain Tom Cairney complained about the rough stuff meted out by those in blue.
"I'm really disappointed that after they kick and kill us, we finish the game with one player less. I really don't prefer to make comments about refs," he aded.
"If I take some action, it will be crazy."