Matthew Upson has admitted West Ham are close to rock bottom after their defeat to Wolves in the battle to stay in the Premier League.
Defensive errors cost the Hammers dearly as they lost 3-1 to Mick McCarthy's side at Upton Park on Tuesday.
Some home fans turned on manager Gianfranco Zola in the wake of the defeat, but England international Upson insists players must take responsibility.
He told the Evening Standard: "We are in a position where, certainly at home in the last couple of games, we have not delivered performances that were acceptable.
"At this stage of the season, looking at our league position, you could say we are close to that point [rock bottom] and perhaps we need to realise that before we can make forward steps.
"It is not a nice feeling, but what we are going to do about it is what we need to be focusing on and there are enough games left for us to accumulate the points we need.
"We need to have a long, hard look and change something about what we are doing. It is up to us, the management and the players, to do something."
Upson added: "It just looks like we have lost that ability to work as a team at the moment.
"We need to go back to basics on that front and realise what we've got to do tactically to get the three points.
"We need to work on that on the training pitch, and probably off it as well, and be more of a group. Hopefully, that will change our performance against Stoke for Saturday."
Upson understands why some supporters vented their frustrations so publicly.
He said: "It is because the supporters are passionate and it works both ways - we are worshipped when it is going great and when it is not, you're at the other end of the stick.
"That is part of the game and part of the pressure of playing for a club like West Ham."
He added: "Is it helpful? Probably not at this time, but it is a test of us as a team - and if you can't deliver then you should not play for West Ham."