Steve McClaren admits that he might have underestimated the size of the task facing him at Nottingham Forest.
Forest have won only one of their first seven league 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 the demoralised boss admitted that Forest badly need a new signing to lift spirits and bolster the squad after a dismal home defeat on Saturday to rivals Derby left the Reds languishing in the npower Championship relegation zone.
Ahead of the home tie against Newcastle in the Carling Cup third round on Tuesday night, 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."