Real Madrid face being without Isco for six weeks - at the very least.
The Malaga-born midfielder is suffering from appendicitis and has undergone surgery, which will require a recovery period of close to a month.
Real Madrid coach Julen Lopetegui said: “I spoke to the doctors today and he has to receive treatment for appendicitis. I hope it goes well and he has a speedy recovery. They did some tests, he will shortly be going in for his treatment. I hope he comes back quickly and finds this same form.
“Any injury is bad news and now we need to find solutions within the squad, let's see who comes in. This kind of thing always happens throughout the season. In this case, it is a shame that he has appendicitis. We have to maintain the faith in whoever we send out onto that pitch."