The Chelsea goalkeeper is expected to join in full training on Wednesday, but Thomas Tuchel has confirmed he will leave it until as late as possible before deciding if his No1 will be fit to face Manchester City in Porto.
Mendy was substituted at half-time against Villa on Sunday after colliding with the goal post.
He underwent scans on Monday and Tuchel confirmed: “The update is that we still have hope that he joins training on Wednesday.
“He made huge improvement in the management of pain. We need a further update, but hope to have him back in training.
“Of course Edouard will play if he is if fit and if he is not fit on Wednesday we will try on Thursday and Friday and we will always be reasonable.
“At the same time we have trust in Kepa. A strong guy on the bench who will take his place.
“The images show the injury is not too serious but every hour counts. We hope he will be on the pitch.”
N’Golo Kante is also due to resume training on Wednesday following a hamstring strain – and Tuchel hinted the France midfielder will also be a starter in Saturday’s final.
“With N’Golo nothing has changed,” said the Chelsea manager. “I think about changing my tactics and just put him in training and put him on the pitch when the game starts on Saturday and maybe I will not speak to the doctors and physios so I hear no more doubts.
“It looks good and I hope it stays like that.”