Barcelona defender Jeremy Mathieu is set to be out of action for an additional two or three weeks after suffering a setback in his recovery from a soleus injury.
The club confirmed the blow ahead of a Copa del Rey visit to Hercules on Wednesday night (30 November), which comes just three days before the long-awaited visit of Real Madrid.
Mathieu, 33, has been hit by numerous injuries since his arrival at Barcelona from Valencia in the summer of 2014. The Frenchman was absent for the majority of last season's run-in after being forced to undergo a knee surgery in March.
The defender recovered in time to feature in the final few games of the season, but another muscle injury ruled him out of Euro 2016.
Mathieu's start to the 2017-2018 campaign has been even worse, making just six appearances for Barca due to various fitness issues.
The defender missed the first Barcelona matches of the season with a thigh injury. He returned to the treatment room in October, after sustaining a calf injury during Barcelona's 1-0 defeat to Espanyol in the Catalan Super Cup.
Barcelona revealed at the time that the Frenchman was expected to be out for three weeks. In an official statement they said: "Tests conducted by the Medical Services on Wednesday morning have revealed that FC Barcelona defender Jeremy Mathieu has injured the soleus in his right foot, which means he's going to be sidelined for an estimated three weeks."
However, more than five weeks later, Mathieu is yet to return. Barcelona have now revealed the Frenchman will be out for at least another 15 days, having suffered a setback in his recovery.
"During the final stages of his recovery, Jeremy Mathieu has suffered a recurrence of the injury to the soleus in his right leg. According the FC Barcelona Medical Services, this means he'll be sidelined for a further 15 to 20 days," the club confirmed. "That means the French defender will be unavailable for the forthcoming games against Real Madrid, Borussia Mönchengladbach and Osasuna."
Mathieu will be joined in the treatment room by Jordi Alba, after the club revealed the Spaniard had suffered an injury during the disappointing 1-1 draw at Real Sociedad, leaving his participation against Real Madrid in question.
In more positive news, Samuel Umtiti has received medical clearance to return to action in the Copa del Rey encounter with Hercules, and should be ready to start when Real Madrid visit the Nou Camp on Saturday if Luis Enrique decides to use him ahead Javier Mascherano to stop Cristiano Ronaldo and Karim Benzema.