The 28-year-old, who was signed for £22 million from Rennes last month, was immediately installed as Frank Lampard’s first-choice goalkeeper at Chelsea.
Mendy was handed his Premier League debut last weekend and kept a clean sheet in Chelsea’s 4-0 win against Crystal Palace.
But Chelsea were handed a scare this week after Mendy suffered an injury during training on Wednesday.
According to The Athletic, Mendy felt pain in his right thigh in the early stages of training and immediately pulled out of the session.
The report claims that Mendy will now be fully assessed by Chelsea as the injury could be a hamstring strain.
Mendy received examinations in hospital in Rabat and The Athletic claims the early diagnosis suggests the injury is only ‘minor’.
It’s claimed that Mendy is also ‘optimistic’ that he will only miss a maximum of two weeks.
Lampard’s side then begin their Champions League campaign against Sevilla on October 20.
Kepa Arrizabalaga kept a clean sheet in Spain’s goalless draw against Portugal on Wednesday night and could be handed a chance to reclaim his place should Mendy be ruled out.