Fabio Coentrao has become the latest Monaco player to suffer injury after sustaining a fractured foot during Saturday's 1-0 Ligue 1 win over Nice.
Adama Traore, Jeremy Toulalan and Lacina Traore have all been missing in recent weeks for Leonardo Jardim's side, and now the coach will have to do without the Portugal international.
Coentrao featured from the start at the Stade Louis II at the weekend, but was forced to leave the pitch after 12 minutes due to injury.
The defender has since undergone further examination to determine the extent of his injury and Monaco have announced he faces a spell on the sidelines, without specifying exactly how long Coentrao will be unavailable.
The 27-year-old joined Monaco from Real Madrid on a one-year loan deal at the start of the season and had developed into an important first-team member in recent months.
He has made 18 appearances in all competitions for the Ligue 1 side, scoring three goals in the process.