Everton midfielder Bryan Oviedo suffered a double fracture of his left leg in Saturday’s 4-0 FA Cup win at Stevenage, an injury which will almost certainly rule him out of the World Cup.
Roberto Martinez’s team were leading 1-0 when the 23-year-old Costa Rica international collapsed in agony after a first half challenge on Stevenage’s Simon Heslop.
He needed lengthy treatment from medical staff before eventually being stretchered off.
Everton team-mates Leighton Baines and Kevin Mirallas were visibly distressed after going over to check on Oviedo.
“Bryan was trying to win the ball but unfortunately I think he has picked up a double fracture, the tibia and the fibula,” said Everton boss Martinez.
“We need to give Bryan as much support as we can now. He’s had a terrific season and I’ve been very impressed with him. He’s an important player in the group and he deserves a speedy recovery.
“The injury to Bryan affected everyone. Those type of injuries leave a sick taste.”
Everton later tweeted that Oviedo would remain in hospital over the weekend and undergo surgery on Monday.
“You won’t meet a nicer human being than Bryan and this was becoming his season,” added Martinez.
“He has shown the quality that he has recently and it’s one of those moments where you feel terribly sad for him because he was in good form and the World Cup was just around the corner for him.
“But now we have to make sure he gets fully recovered and he comes back as important player as he has been for the club recently.”
Martinez insisted Heslop should not be blamed for the injury.
“It was a very unfortunate action, nothing malicious,” the Spaniard said
Oviedo is unlikely to recover for the World Cup in Brazil which starts on June 12 and where Costa Rica face England, Italy and Uruguay from Group D in the group stage.
Oviedo, who can also play at left-back, moved to Everton from Danish side Copenhagen in August 2012 for £5m (Dh30.3m).
Later Saturday, Oviedo wrote on Titter: “Thank you everyone at this difficult moment. You all are in my heart.”