Luis Suarez could be sidelined ahead of the World Cup after reportedly injuring his knee during a training session.
Liverpool are awaiting an update from their own medical staff after reports in Uruguay that the striker requires an operation.
The player was apparently injured during a training session with his national team - who are one of England's opponents at the World Cup - after arriving back in his homeland on Tuesday.
It was reported the 27-year-old could undergo surgery in the next few hours to repair damage to the meniscus in one of his knees.
There has been no official confirmation from the Uruguay Football Federation on whether an operation will take place, but it is expected to make a statement later on Thursday.
England play Uruguay in Group D on June 19 in Sao Paolo.