The striker was forced off against Burnley at Turf Moor last night with an injury.
Alan Pardew (talking to Sky Sports): “We lost Sammy, by the looks of it, to an injury, so that’s bad news.
"But we don't know how bad it is and I'm sure it is too early to rule him out of Saturday's game against Chelsea.
"We will wait and see, but we will have Moussa Sissoko and Jack Colback back from suspension for Saturday’s game and that is a major plus.
"Fabricio Coloccini could also return from injury, but we will look at that more nearer to the day."