Atletico Madrid striker Luis Suarez could yet make their clash with Barcelona this weekend.
Sport says the striker tested positive for coronavirus this week while with Uruguay and missed his country's loss to Brazil on Tuesday.
However, Suarez hopes that the result was a false positive and that a new test returns a negative result before this weekend's meeting at the Wanda Metropolitano.
He will be tested on Wednesday and will then know if he will be able to return to Atletico training ahead of the game against Barça in LA Liga.
The Uruguayan Football Association revealed that Suarez had tested positive on Monday, saying that he was "healthy" and not experiencing any symptoms.
If a second test comes back positive, Suarez will also miss the Champions League game against Lokomotiv Moscow next week.