Coventry full-back Dan Fox looks set to miss the FA quarter-final tie at home to Chelsea on Saturday after injuring his knee against Sheffield United.
The Sky Blues lost the game with the Blades 2-1 at the Ricoh Arena on Wednesday as the 22-year-old was forced off at half-time.
The former Walsall man is highly rated at the Championship club and was linked with a move to Newcastle in the January transfer window.
The news is likely to be a big blow for manager Chris Coleman as he eyes a cup shock but the Welshman insists he would rather have his charge fit for the upcoming league games.
"We will have to wait and see but at the minute it doesn't look very good," he said.
"I am not saying long-term but, he could struggle for the weekend. But I am not too bothered about him missing Saturday.
"I would much rather have him fit and available for the league games against Bristol City and Preston."