Sam Allardyce is hoping West Ham United can reproduce their fine performance against Manchester United of ten days ago in Wednesday's FA Cup with Budweiser third-round replay, despite having to cope with a shortage of defensive personnel.

James Collins' hamstring injury, sustained in Saturday's 3-0 defeat at Sunderland, leaves Big Sam with only three senior defenders to call on. However, he is still banking on another competent rear-guard display at Old Trafford.

The Hammers conceded after just 32 seconds in a 1-0 Barclays Premier League defeat at Old Trafford in November, but then kept Manchester United's array of attacking flair at bay for the remainder. Big Sam insists it will require a similarly stoic effort to produce a positive outcome on Wednesday evening.

Sam, could you start with the team news for Wednesday's trip to Old Trafford?

SA: "It's not great from a defensive point of view with James Collins going down injured and with both George McCartney and Joey O'Brien unavailable. So it's very desperate in that particular area which is one thing, with the window being open, I can do something about. It's less than the bare bones at the moment, so it gives me great difficulty going to Old Trafford with only Guy Demel, James Tomkins and Winston Reid of our senior defenders fit. After that we're down to young lads like Jordan Spence and Danny Potts.  In front of that it is looking alright. I think the rest of the team are getting there. Mohamed Diame is back with us, which is good news, and we're still waiting for Andy Carroll to join up with us again."

Given your injury worries, is it tempting to rest some of your more senior players?

SA: "I can't rest any of the defenders. The trouble is, if I don't rest them and they get injured, I'm in trouble against Queens Park Rangers on Saturday. If I lose any of those senior three, I move into bigger problems. We'll have to take a big look at the squad and try to plan a different way of playing as well as a team that's going to be quite different, based on the number of injuries I've got and the big game we've got on Saturday as well."

How difficult will it be to repeat the two very good performances you've given against Manchester United this season?

SA: "Obviously it will be more difficult to beat Manchester United on their own patch than it would have been at the Boleyn Ground a week ago. I think that was a huge effort that we gave, which nearly brought us a fantastic result. But unfortunately, because of that man, Robin van Persie, it was snatched away from us at the very last gasp - which is something Manchester United have always been capable of doing.

"It was a huge disappointment on the day and all we have to do tomorrow night is just to enjoy the game, play our best and see where that takes us. And if we put our best performance on, you can ask no more than that. The challenge is set for the players that start the game and hopefully they'll know they have to play to their best at Old Trafford.

"We did very well there in the league, after recovering from a very tricky start, with a deflected own goal after 30 seconds. So we did very well to stifle Manchester United's huge amount of flair on the frontline and we've obviously got to do that again."

What can you tell us about new signing Wellington Paulista?

SA: "I think he's a talented player in terms of his ability on the front line. Let's see if we can apply the talent into the team as quickly as possible. I don't know how quickly that's going to be, sooner rather than later hopefully, but it might take a little while. Talent is the most important thing and then applying that talent where it's most difficult in the Premier League and that's in the final third."