Andre Gomes was rushed to hospital after suffering a horror injury against Tottenham on Sunday.
The Portuguese midfielder was left helpless on the ground with his right foot hanging at 90 degrees after being brought down by Son Heung-min.
Everton’s medical team attended to the player instantly and stretchered him off after an eight-minute delay.
It was confirmed soon afterwards that the player had been taken straight to hospital after coming off the pitch.
“Andre Gomes went to the hospital. Our medical staff is taking control of everything and soon there will be more information,” Everton boss Marco Silva said.
“We wait until it is a bit more clear. It is a bad moment for us as a group and as a team. It more than a football game, this is the most important thing right now. We as a group have to keep togetherness.”
Doctors will ascertain exactly what injury Gomes has suffered but whatever the diagnosis he is expected to be sidelined for a long while.
Son was sent off for the challenge despite the fact referee Martin Atkinson originally drew a yellow card from his pocket.
The South Korean’s petulant challenge from behind sent Gomes tumbling into a collision with Serge Aurier.
It is unclear exactly what part of the incident caused the horrific injury but both Tottenham players were reduced to tears after seeing Gomes’ leg.
Jamie Carragher thought it was harsh to send off Son as did many other fans watching on.
“It’s not a red card,” Carragher said on Sky Sports commentary.
“Son is just trying to stop him in his tracks and Gomes’ foot just gets caught underneath him. Aurier comes in behind but it wasn’t either player, really.
“The challenge from Son forces him to ground and he gets his foot underneath him as Aurier come in.”