Danish defender Daniel Agger admits he "does not have a clue" what has gone wrong with Liverpool's defending this season.
Liverpool's leaky defence has been blamed for the club's worst run of form for 22 years, with six defeats already this term and 17 goals conceded in their first 13 matches.
Last season Liverpool let in just nine in their first 13 games, and were second in the Premier League at this stage.
Now they are eighth and aware that if they lost at home to Manchester United on Sunday, it will be their fifth successive defeat and their worst run since 1953.
Injuries to Agger and Martin Skrtel, the departure of Sami Hyypia and a poor start to the season by Jamie Carragher has all contributed to the current crisis.
Agger said: "We must defend as a unit, it is not just about four men at the back. Conceding goals like we are is just not good enough.
"We are normally so strong and we don't concede goals like that. What is wrong? To be honest I haven't got a clue.
"I feel okay, but I am not 100 per cent fit after my back problem. I need match fitness, but that will return slowly."
He added: "Defeats do affect the team, but everyone just has to carry on, work hard, and things will be okay.
"We need to learn to play consistently through a game, that's simple really.
"We were at home against Lyon in the Champions League on Tuesday, we should have been able to finish the game off a long time before they scored. We were leading and missed good chances that could have wrapped things up.
"In the end it showed that we were not good enough. We have to address that. It is Manchester United next, so we have to raise ourselves for that.
"It is all about hard work. If you are not playing well that is the way to improve. Everyone must be focused now."
Liverpool boss Rafael Benitez will wait until the last moment before deciding on his team, giving Steven Gerrard, Fernando Torres and Glen Johnson - all groin injury victims - every chance of proving their fitness.
On his own position, after four defeats on the trot, Benitez said: "I am relaxed. I know how we are working every day, the players know too. In the past we have been very good and the situation and players has not changed too much.
"It is about confidence and winning that first game. If we want to change things we must focus on football and not what is going on off the pitch here.
"We have done extra training sessions, the attitude of the players has been good and you could see how focused and positive they are.
"They know the situation. They know what they must do, and they will try to do everything we are asking of them.
"The team is not as bad as people think. We have beaten United without Gerrard and Torres and we know that we can beat anyone. We have total confidence in that."
