Everton could be without new loan signing Eliaquim Mangala for the rest of the season after manager Sam Allardyce admitted the defender is out "long-term".
Mangala was forced off in the first half of Everton's recent fixture with Crystal Palace and is believed to have damaged ligaments in his knee.
The Frenchman was brought in during the January window from Manchester City to bolster the Toffees' back-line, though his spell on Merseyside may already be over.
Speaking this week from Everton's warm weather training camp in Dubai, manager Allardyce outlined his fears that Mangala's injury is as serious as first believed.
"The injuries this week were a blow, with Mangala in particular - that looks like it could be long-term, which is a great shame for him and for us because I think he was a very good addition to us," Allardyce told evertontv.
The full extent of the 27-year-old's injury is expected to be learned in the coming days.
Despite the loss of Mangala, Everton went on to defeat Palace in their last Premier League outing and Allardyce now feels the club will benefit greatly from their Dubai break.
"We've been able to relax together and work hard together and I think it has helped bring relationships closer.
"Some are already friends and some will have made bigger friends with others and, of course, the big thing about it for us all is to get to know each other better - not just the players but the players and the staff as well."