Andy Carroll's latest comeback has been delayed with no return in sight for the injury-plagued West Ham striker.

The 27-year-old, who has started just 38 Premier League matches in over three years with the Hammers, picked up a knee problem in the Europa League tie with Romanian side Astra Giurgiu in August.

The initial prognosis was that Carroll would be sidelined for four to six weeks, but over two months later the former Newcastle and Liverpool frontman is no closer to returning.

Manager Slaven Bilic said: "It was a very strange injury. He stayed on the pitch for the whole game and I didn't even notice he got injured until the end of the game or the next day when we did all the scans.

"Originally it was four to six weeks - and we were fuming about it, it was a shocking prognosis - but now it's way longer than that so all that I can say is he's working really hard, he's progressing, but its slower than we expected.

"He's progressing but it's not at the speed that we wanted and he wanted. He's working hard and getting better every day, but unfortunately he's still not ready to train with us.

"All I know is that it's about weeks - but then it was about weeks at the beginning when it happened."

Bilic has at least been boosted by the return to training of club-record signing Andre Ayew ahead of schedule.

The Ghana forward, who joined the Hammers from Swansea in August for £20.5million, sustained a thigh injury half an hour into his debut against Chelsea.

Ayew rejoined his team-mates on the training pitch on Monday and has an outside chance of being in the squad to face Sunderland at the weekend.

"We were expecting him back later, in December or late November, so we are delighted that he's back and now we're going to see," added Bilic.

"He looks good in training and we're going to try to prepare him for games as soon as possible. We have a couple of sessions before the game against Sunderland and then we'll see.

"If we talk about Saturday I'm not going to rule it out, but it's unlikely."