Chelsea manager Roberto Di Matteo has urged Manchester United boss Sir Alex Ferguson to focus on his own side rather than comment on the affairs of others.

Chelsea's preparations for their trip to Swansea have been overshadowed by the events of recent days, which have seen the Blues report referee Mark Clattenburg for using "inappropriate language" towards John Obi Mikel during their loss to Manchester United.

The matter is subject to police and FA investigations and Blues boss Di Matteo did not want to be dragged into the matter. United boss Sir Alex Ferguson has had his say on the subject, claiming "I don't believe Mark Clattenburg would make any comments like that. I refuse to believe it."

Di Matteo was not keen to comment on the matter but he did urge Ferguson to focus on his own side.

"It's a free country where everybody has the freedom of speech," Di Matteo said in reference to Ferguson's comments on Clattenburg. "We'll take into consideration what other people say and use it as a motivational tool for ourselves.

"He likes to talk about other clubs. We tend not to. I'll leave it up to him."

Di Matteo has confirmed Mikel will be in the travelling party as he is convinced his midfielder is in the right frame of mind.

"He is alright," Di Matteo said. "His frame of mind is good. He is focused on training and playing and will be ready.

"He will be available yes. I have spoken to him and he is fine."

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