The right back who joined City from Sunderland was booked during the win against Wolves and is suspended.
"I would rather lose Wrighty in the FA Cup than the League," said Chris Coleman to the CT. "If I am honest, that is our bread and butter.
"That is not to say that the FA Cup is important because it is and we have got a chance to get into the Quarter-Finals.
"It will be tough for us and if we manage to get past them, it will keep the excitement going and keep our fans coming back."
Winger David Bell is cup-tied for the match but Aron Gunnarsson is available after serving a two game suspension.