Named and shamed: Chelsea yob who allegedly made 'monkey' gesture at United ace Welbeck
The Blues boss refused to be drawn on the issue in any depth, citing the matter was in the hands of the police and FA.
But responding to the Manchester United manager's comments questioning the credibility of the claims he said: 'He likes to talk about other clubs. We tend not to. I'll leave it up to him.
'It's a free country where everybody has the freedom of speech. We'll take into consideration what other people say and use it as a motivational tool for ourselves.'
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Not impressed: Roberto Di Matteo plans to use comments as a motivational tool
Asked if he feared referees might treat the club differently after making the accusations against Clattenburg, the Italian said: 'I really hope not. I believe that they won't. We have faith in the referees. They are people that are under a lot of pressure.
Centre of the storm: John Obi Mikel (right) training, with Fernando Torres (left)
Di Matteo maintained his stance of silence when asked about the Chelsea fan caught making a 'monkey' gesture during Wednesday's Capital One Cup tie but did suggest the manner in which racist incidents have been highlighted proved there was still work to be done.
Mikel in the middle: Branislav Ivanovic and Gary Cahill either side of the Nigerian anchor man
'The fact that these incidents are happening give a lot of media exposure and makes people aware that we have to fight maybe a little more strongly than perhaps we thought. Everyone has to be involved in this process to eradicate it from the sport and life in general.'
Larking around: Darren Fletcher (left) and Robin
van Persie appear in relaxed mood ahead of tomorrow's cruch clash at
Old Trafford
Best bib and tucker: Rio Ferdinand chucks a
training vest away (left) as some United prankster throws a bit of turf
and left-back Patrice Evra (right) ahead of tomorrow's match against
Arsenal
The Metropolitan Police and the FA are investigating an allegation that Clattenburg used 'inappropriate language' towards Mikel during the game in which he sent off two Blues players as they went down 3-2 to Ferguson's side.
Support: United boss Sir Alex Ferguson, taking training at Carrington, has pledged his support to referee Mark Clattenburg
'I think it’s unthinkable. It’s unthinkable in the modern climate. I just don’t believe it.
'There’s no way a referee would stoop that low. I’m convinced of that.
'If you look at the modern game compared to 25 years ago it’s completely changed. I know the banter between players and referees 25 years ago is completely different.
'I have never heard a player come to me in the last 15 years and say a referee has sworn at them during a game, ever.
'This is where I stand on this issue with Mark Clattenburg. I just don’t believe it.'
Ferguson joins Arsenal manager Arsene Wenger in standing by Clattenburg.
On Thursday, Wenger said: 'I didn’t follow the whole (Chelsea) story completely (but) my opinion is just when I didn’t behave well I have an explanation with the referee at the end of the game or another day, rather than going public with little proof. I’m not in favour of making these things public.'