Manager Sam Allardyce believes he will be forced to play a game of 'Call My Bluff' this month as he bids to solve West Ham's defensive dilemma.
James Collins' hamstring injury suffered in a 3-0 loss at Sunderland means Guy Demel, James Tomkins and Winston Reid are the only front-line defenders available for tomorrow's FA Cup third-round replay at Manchester United.
It means Allardyce could change his system at Old Trafford, rather than promote youngsters, with crucial games coming thick and fast this month.
"I've got to strengthen our defensive areas," Allardyce said.
"It's less than the bare bones at the moment. It gives me great difficulty going to Old Trafford tomorrow."
The predicament makes life difficult in the transfer window, with Allardyce keen to add to his defensive options.
"What you don't want to be is like what we are, which is a little desperate because of our injury problems," he added.
"At this stage of the season it's 'Call My Bluff'. You say no, they say no and then you sit and wait and bite your fingernails and hope they change their mind and say yes.
"That's why so much happens in the last week of the January transfer window.
"It's more expensive at this stage of January than it is at the latter stage of January."
Allardyce dismissed reports linking fit-again midfielder Mohamed Diame with Arsenal and insisted the Hammers have not made a further bid for Blackburn's Martin Olsson.
Allardyce added: "We've had no bid or official bid at all from Arsenal for Mo Diame and I can't see where he's going to fit in. I can't see who he's going to replace.
"There wouldn't be any point in him going unless he's playing, would there?
"We've not made any further enquiries or any further bids for Martin Olsson. We haven't got the funds to go in with a higher bid."
With Barclays Premier League matches against QPR and at Arsenal in the next week and a total of four matches remaining in January, Allardyce is aware rotation is required, but he is hamstrung over his defence.
The schedule makes recruitment a challenge too as any new arrival must be ready to play immediately.
"The one area I should rest is the defenders, but I can't," said Allardyce, who is still deliberating how best to integrate new signing Wellington Paulista into the side.
"If I don't rest the defenders and they get injured, I'm in bigger trouble against QPR on Saturday.
"Until we get those injuries back we're in a delicate position in terms of the amount of games we've got as well.
"There's this one, then there's Saturday, then we're fitting Arsenal in that got cancelled on Boxing Day. Then there's a midweek fixture for all of us in the Premier League at the back end of January as well.
"It's about getting players in who have the experience and the talent and hopefully the determination to get through that period with more victories."
A place in the fourth round of the FA Cup is the target tomorrow night against a Manchester United side which narrowly stayed in the competition at Upton Park 10 days ago. The Hammers lost 1-0 in the league when the sides met in November.
"It's more difficult to beat Manchester United on their own patch than it would've been at Upton Park a week or so ago," Allardyce added.
"That was a huge effort that we gave that 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 of the game. That was a huge disappointment on the day.
"We did do very well in the league, after recovering from a very tricky start with the deflected own goal after 30 seconds.
"We did do very well stifling Manchester United's huge amount of flair on the front line.
"We've got to do that again and to get through we've obviously got to get a goal or score more than Manchester United do."