Everton fear rising star Ross Barkley could be out for several weeks with a foot injury.
The midfielder was forced to miss the Toffees' 2-0 Barclays Premier League win over Norwich at Goodison Park with what could be a broken toe.
Barkley suffered the injury during the FA Cup third-round win over QPR last weekend, a match in which he also scored.
Manager Roberto Martinez said: "We are going to assess him and it seems he is going to be out for a while. It could be broken.
"We are going to assess it to see if there was displacement or not. It is a very similar incident to the one Leighton Baines had.
"Before we say exactly what it is, that is the fear, that there could be a fracture in his toe."
Left-back Baines returned to action at Christmas after a month on the sidelines with his injury.
Barkley, 20, has made a huge impression this season having been given regular first-team opportunities by Martinez.
His performances have also earned him three England caps and he is firmly in the reckoning for a place in Roy Hodgson's summer World Cup squad.
The injury will not prevent Barkley travelling with the squad to a warm-weather training camp in Tenerife ahead of next week's trip to West Brom.
Martinez said: "Knowing Ross, being a young man, hopefully with the sun - a bit of vitamin D intake, it will accelerate the (healing) process."