Fullback Cédric has not recovered in time to make Sunday's trip to Bournemouth, after an early departure against midweek opponents Man City, Mauricio Pellegrino confirmed.
The manager also cast doubts over Shane Long, who is suffering with a calf problem, but asserted that the striker will continue to be monitored in the lead up to this weekend's Premier League action.
Pellegrino said: "Cédric will not be ready for Sunday, and Shane Long has got an issue in his calf. So we've got some players with a problem today.
"Maybe tomorrow we'll review, and we'll decide how he [Long] is. The doctor will check, but today he couldn't train, it is a little bit sore in the calf. Tomorrow we'll make a decision.
"Most of my players are ready to compete and with the fixture calendar we have in the next two months, that is good news for us."