The Nigeria midfielder has been at the centre of the latest controversy hanging over Stamford Bridge following last Sunday’s defeat by Manchester United, with Chelsea lodging an official complaint with the Football Association alleging referee Mark Clattenburg used “inappropriate language” towards Mikel.
The Metropolitan Police launched an investigation into the comments alleged to have been made by the official earlier this week.
But Di Matteo, whose side travel to the Liberty Stadium on Saturday afternoon, is convinced that the 25-year-old will not be distracted by the off-field issues.
“His frame of mind is good,” said the Italian on Friday at his weekly news briefing. “He’s focused on training and playing well. He’ll be available for tomorrow [Saturday]. I’ve spoken to the player and he’s fine.
“He’s a very strong character and he has a very strong personality. He’s shown that in his performances and he’s been able to play well under this pressure. From what I can see, he’s dealing with these issues in a good manner.”
Meanwhile, the Chelsea boss looks likely to be without Juan Mata (hamstring) and David Luiz (ankle) for Saturday’s clash.
“We’ve got a few issues with a couple of players. Juan Mata is struggling with his hamstring and David Luiz with his ankle. There are a few others that have a few niggling injuries too.”
John Terry will serve the final game of his four-match ban for using racist language towards QPR’s Anton Ferdinand on Saturday.
And although Di Matteo admits the centre-half has been a loss, he does not believe his absence is solely to blame for the Blues having shipped 10 goals in their last three outings.
“In the last few games we’ve conceded a few more goals than at the start of the season,” he said. “It’s been down to a few individual mistakes but our track-record is quite good.
“He’s obviously an influential player for us and a fantastic defender. The other players have done a fantastic job when they’ve come in but certainly Terry is a player that we miss.
“We have to improve but I don’t think it’s just as simple as that. You look at other teams and they’re conceding goals. But we certainly have to improve our defensive organisation.”
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