Everton say defender Ramiro Funes Mori is likely to miss the rest of the season after suffering a torn meniscus playing for Argentina against Bolivia earlier this week.
"It has been confirmed that the defender suffered a torn meniscus in Argentina's 2-0 defeat to Bolivia on Tuesday evening," said a statement from Everton.
"He will have a surgical opinion next week but the initial diagnosis suggests the 26-year-old is likely to be out of action for the rest of the campaign."