Steve McClaren admits he might have underestimated the size of the task facing him at Nottingham Forest.
Forest have won only one of their first seven npower Championship matches since the former England head coach arrived at the City Ground in the summer.
McClaren says his time in charge of the East Midlands club has been among the most frustrating periods of his managerial career.
And he admits Forest badly need a new signing to lift spirits and bolster the squad after a dismal home defeat on Saturday to Derby which left the Reds languishing in the relegation zone.
Ahead of tomorrow's home tie against Newcastle in the Carling Cup third round, McClaren said: "I knew it was going to be difficult. I said before that it was a work in progress, I should have said that it was a lot of work in progress.
"Frustrating is a good word. I have been frustrated every day since the first day I came here.
"It has been the tradition for this club in recent years to start slowly, but we have already highlighted the reasons why that has happened in the past. We have not addressed that this season and now the club has had another slow start.
"When you lose nine players and replace them with five, you will be short. It is now affecting everyone. New faces lift the spirits at clubs.
"We have been trying to do that, but without success. The quality of player who might make a difference, the quality of player we want, is either not available or too expensive for us."
Forest have lost their last three league matches and McClaren is demanding an immediate improvement in performance against Newcastle, but reiterated that he will require board backing in the long term.
"We let the fans down on Saturday. It will be a long time before we can go out in Nottingham again - and rightly so," the Forest boss said.
"The fantastic support here deserve better - it was unacceptable. We were totally lacking in the aspect of mentality and character.
"But we have the chance to regroup when we play Newcastle and, whoever shows up, we have to produce a performance to be proud of. Whatever stick we get we deserve and we have to regroup and look to Tuesday and make it never happen again.
"Hard work on the training ground can get it right for us. Football is a cruel game and I have been hurt and had down times many times before, I hope this is the lowest Forest can go."
McClaren added: "We have to recover, we have to bounce back. It is up to us, as a club, to say, 'What are the problems? How can we help you? What do we need?'.
"We need to do work on and off the field."
Defender Chris Cohen is nursing a knee injury sustained on Saturday. He joins midfielders Paul Anderson (hamstring) and George Boateng (ankle) on the sidelines, while Dexter Blackstock and Garath McCleary remain long-term absentees.
Goalkeeper Paul Smith, defenders Brendan Moloney and Joel Lynch and forwards Lewis McGugan and Robbie Findley are available should McClaren wish to make changes.Reuse content