The striker is yet to feature for the Hammers since making his loan move permanent during the summer, while the manager has revealed Carlton Cole is back training with the squad
West Ham manager Sam Allardyce has been left "frustrated" by Andy Carroll's latest injury setback.
The England international has not played for the club since damaging his heel on the final day of last season, and will now continue to seek specialist advice on his latest injury setback.
It was thought that he had suffered an Achilles problem, but West Ham confirmed on Friday that the issue is with his plantar fascia and Allardyce has describing the setback as "hugely frustrating".
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He added on the club's official website: "It's the same type of injury (to the heel problem) but in a different area. It is not an Achilles injury, as has been suggested, but instead it involves the band of tissue which runs under the foot.
"According to the specialist, the chance of a recurrence of that type of injury is about four per cent but unfortunately for Andy, he was one of the unlucky ones.
"We had been very cautious, very patient with him along the way and it's sad this has happened for him as well as us.
"He doesn't need an operation but we need to give the foot time to re-heal, continue the rehab and get him back in training again."
Allardyce added that Carlton Cole may yet re-sign for the club to boost his attacking options, having left Upton Park in May following the end of his contract.
"We've offered training time to Carlton, for him to try and help him get fit if he wants," Allardyce confirmed.
"If he's happy with that, I would be, and we'll see where we are from there, because we still have one place left in the squad."
Allardyce is without Carroll, Stewart Downing (leg), George McCartney (knee) and Joe Cole (hamstring) for Sunday's game.