Rangers star Glen Kamara will be called for cross-examination as Ondrej Kudela's hearing at the Court of Arbitration for Sport is delayed until April.
The Slavia Prague defender was found guilty of racially abusing the Finland international in the second leg of the Europa League tie between the two sides in 2021.
A UEFA investigation found that he had called the Rangers man a "f*****g monkey" and Kudela was hit with a 10 game ban.