Sunderland have appealed against the red card midfielder Didier Ndong received in Saturday’s 4-0 Sky Bet Championship defeat at Cardiff.
Ndong was dismissed by referee Andy Madley for a challenge on Junior Hoilett four minutes after half-time.
Manager Chris Coleman admitted in his post-match press conference that the Gabon international had “given the referee a decision to make”, but Press Association Sport understands that the Black Cats have now challenged the decision.
If the appeal fails, Ndong faces a three-match ban, something which could hamper his efforts to leave Wearside this month.
The 23-year-old, a £13.6million signing from Lorient in August 2016, has told the club he wants to go and the Black Cats will hope to recoup a significant proportion of that fee in the face of ongoing financial difficulties.