Crystal Palace's Wilfried Zaha has joined the club's long list of injured players with a hamstring problem and manager Roy Hodgson said he was not sure how long the winger would be out.
Zaha, Palace's top scorer with nine Premier League goals this season, was forced off during their 2-1 win at Newcastle United on Wednesday.
"We don't know how long it's going to keep him out," Hodgson told reporters ahead of Monday's league trip to Leeds United.
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"He certainly won't be available for this game, and it could be much longer than that. At the moment of course it's the early stage of the injury and he's still being assessed."
Hodgson said the club's medical staff are doing everything to ensure a quick recovery for Zaha.
"You never know with these hamstring injuries, but Wilf is incredible in terms of recovery so I wouldn't want to put a definite timeline on it," he added.
"But it's a muscle strain and all muscle strains take time to heal. Our people are doing their level best to get him back on the field."
Palace have been without Wayne Hennessey (thigh), Nathan Ferguson (knee) and Connor Wickham (thigh) for most of the season, while Mamadou Sakho (thigh), James Tomkins (eye) and Jeffrey Schlupp (hamstring) have joined them in the treatment room.
James McArthur (muscle) and James McCarthy (groin) were also missing from the matchday squad against Newcastle.
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