Enzo Fernandez has left the Argentina camp due to an issue in his right knee in what is a fresh injury concern for Enzo Maresca and Chelsea.
The 24-year-old midfielder started for his country in the 1-0 friendly win over Venezuela in the early hours of Saturday morning. Fernandez made more passes than anyone else during his 78 minutes on the pitch, before being replaced by Alexis Mac Allister.
Argentina confirmed on Saturday, though, that Fernandez has now left the camp and will not feature against Puerto Rico in the early hours of Wednesday. The midfielder will now return to London where he will be assessed by Chelsea's medical staff.
In a statement Argentina said: "The Chelsea footballer Enzo Fernández has been withdrawn from the tour due to synovitis in his right knee."
The news will be a huge worry for Maresca with Chelsea next in action against Nottingham Forest on Saturday. The Blues then face Ajax on Wednesday, October 22 before welcoming Sunderland to Stamford Bridge three days later.
Chelsea are already without Cole Palmer, who is expected to be absent for the remainder of the month as the 23-year-old continues to recover from his persistent groin injury. Palmer is expected to miss at least four matches for the Blues, with the club anticipating the England international to be out for weeks, rather than months, football.london understands.
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