Everton have revealed that Bryan Oviedo has suffered a double fracture in his left leg.
The 23-year-old Costa Rican suffered the injury in the 20th minute of his side's 4-0 away win against Stevenage in the fourth round of the FA Cup.
Oviedo was immediately substituted and taken to hospital, and the extent of his injury has now been announced.
"Bryan has broken two bones in his left leg," reads a statement on Everton's official Twitter page.
"He will remain in hospital over the weekend and have an operation on Monday."
Oviedo joined Everton from Copenhagen in 2012.