NEIL Lennon has revealed Celtic are currently undergoing a revamp of their scouting and recruitment system in the wake of supporter criticism about the club’s recent record in transfers.

The disaster of Tuesday night’s Champions League exit to FC Cluj of Romania sparked fierce criticism over the lack of quality signings made in recent seasons, despite the record for transfer fees received being broken three times in the past four years.

Celtic are cash rich, with an estimated £40million-plus in the bank, but this is the third season in a row when they have lost in the qualifiers to a club with far less resources.

Lennon claimed the club had been in a void since the much-criticised former head of recruitment, Lee Congerton, left in May and the appointment a month later of Nick Hammond who for the moment has taken the role on a temporary basis.

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However, the Celtic manager moved to calm the fears of fans and insisted work was going on behind the scenes to improve this aspect of the club.

Lennon said: “We do have a rebuilding job on the recruitment side - there is no question of that. We are trying to do that and Nick is working to rebuilt the recruitment department.

"Lee left in the summer and that created a void. Nick will hopefully be in permanently and hopefully he can build his own ideas there. That's what we are looking for him to do.

"It's been difficult with so much change and that's the part the public don't see. We are working really hard in the background.”

Chief executive Peter Lawwell has been the focus of much of the criticism, the perception being that he and the board’s refusal to spend more on new signings have left Lennon with an inferior team compared to the one Brendan Rodgers had in his first season.

Lennon said: “I don’t know about how much money we’ve got. You can analyse it to death but we had enough to get through but we didn’t’. We have to look at ourselves and be united.

“The board have been brilliant with me. The players are hurting but they are hungry to bounce back. We all wanted the Champions League. I wanted it. I’ve been there before, I’ve been through the groups, I know what it means as a manager to perform at that level.

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“But we have to accept it’s not going to be this year. We will see where the Europa League takes us and it’s a big domestic campaign. Yes, it’s a bitter blow because I wanted it as much as anyone, but we’ll get over it.”

Lennon has not escaped the supporters' ire. His decision to drop Boli Bolingoli, a £3m summer signing, and replace him at left-back with Callum McGregor has been blamed in some quarters for what was a shock European defeat.

He said: "It’s expectation. I’ve lived with it for a long, long time. It’s going out of the Champions League that hurts everyone because of the gravitas and what it means to the supporters – they crave it. I don’t understand the vitriol at times but you accept that as well.

“I can understand people wanting to have a stick to beat me with in terms of team selection.

“But, while I’m not huge on stats, we scored three goals at home which I would have taken before the game.

“We had 20-odd attempts at goal and dominated possession. As a manager, you particularly look to attempts at goal because that’s when you know it is working.

“The psychology of the game is that we were flat or a little bit passive in the first half, which is not what we want from the team.

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“We analysed it this morning for 15 minutes and let the players see for themselves what we are looking for. We are looking for a lot more, especially in the first half.

“At Celtic Park on a European night, we have to be at full throttle."

AIK Stockholm, the champions of Sweden, come to Celtic Park on Thursday for the first-leg of the Europa League group stage play-off.

Dunfermline come to Glasgow this afternoon for a Betfred Cup tie and Leigh Griffiths admitted his team cannot afford to dwell on what was a huge disappointment.

The striker said: "It’s not been great but we can’t dwell on it; we need to pick ourselves back up. Yes, it was disappointing but it’s in the past and we need to move on from it and put things right.

“Obviously, playing in the Champions League is the pinnacle of your club career but you can’t not turn up for the first 45 minutes and expect to go through.

“If we’d played the same way in the second half right from the start we wouldn’t have had any problems but we weren’t good enough. I know we lost goals in the second half but that’s because we were pushing for that extra goal ourselves. You’d rather lose by going out fighting than sit back and try and snatch one on the counter.

“Dunfermline will come and make things difficult for us. We’ll respect them but it’s up to us to go out and win comfortably. It’s about us trying to put in a performance to get bums on seats. It will be far from a sell-out against Dunfermline and we ‘ll need Thursday to be a sell-out because it’s a hugely important game for the club.”