Duberry has only just signed a new five-year deal at Elland Road, but he has failed to break back into David O’Leary’s first team.

But with transfer cash limited at Parkhead, the Celtic manager has denied making contact with the Yorkshire outfit.

O’Neill said: ‘‘If you are asking me whether I have made any approach to Leeds United then the answer is no.’’

He has been left short at the back with an ankle injury to promising youngster Stephen Crainey, who was hurt at Dundee United on Saturday.

He already has Chris Sutton and Didier Agathe injured and revealed today that Crainey would be out for over a month.

‘‘He’s got a similar sort of injury to Chris Sutton,’’ added O’Neill. ‘‘Although I don’t think there’s much damage he is looking at four or five weeks out from when it was done.

‘‘It’s really unfortunate because he’s been doing splendidly well for us.’’

O’Neill is hoping Sutton can return to action quicker than first thought.

The £6million striker was injured against Livingston last week and doctors ruled him out for over six weeks.

But O’Neill said: ‘‘It’s looking like he could be out for six weeks, but I’m hoping that he comes back quicker because he’s a good healer. If he comes back before that then I would be absolutely delighted.’’

Referees have come under fire after some controversial decisions but the Celtic boss refuses to point the finger and today jumped to the defence of Scottish referees.

Official John Rowbotham was criticised after failing to punish a number of Dundee United players, including Jim Hamilton who injured Crainey with a bad tackle but booked Alan Thompson for a seemingly innocuous challenge.

But O’Neill said: ‘‘I’m not sure how Alan got it, whether he said something, but I don’t want to get embroiled in any particular incident as there’s no point.

‘‘But I think the refereeing standard is high. Everyone seems to call them a lot, but I’ve been particularly impressed with certain things from them.

‘‘I think that challenge on Stephen Crainey got people a little bit wound up, but I’m just delighted we won that game.’’

That victory maintained their 10-point lead at the top of the Scottish Premier League before tomorrow’s visit of strugglers Motherwell.

The game sees a reunion of old friends and Wales international team-mates John Hartson and Karl Ready.

The 26-year-old admits he is relishing the battle, but admits it will be difficult to play against the defender.

Hartson joked: ‘‘He’s a big strong player and very tough, but I won’t be able to smash him for a start.

‘‘I know him having played for Wales with him and I don’t particularly like playing against my mates.

‘‘Maybe you’ll think a bit more when going in for challenges. Anybody will tell you that they don’t love playing against their mates especially the way I play, but there’s nothing malicious.

‘‘I think we’ll have a good battle against him and we’re both professional enough, but we’ll have a drink after it.’’

Motherwell’s Irish international striker David Kelly is relishing playing in front of a full house at Parkhead.

The veteran was in regular attendance for Celtic’s European matches and he cannot wait to taste the atmosphere again.

Kelly said: ‘‘I am very much looking forward to this match.

‘‘I have played at Celtic Park a few times. I also went to see Celtic playing in their European matches and the atmosphere at the Valencia game was astonishing.

‘‘What a boost it must be for the players to play in front of a home crowd such as they have.’’