Chelsea face referee backlash if accusations against Mark Clattenburg are baseless

Chelsea will face a backlash from referees and officials should their race abuse allegations against Mark Clattenburg prove baseless, with the game's top officials likely to press for a sanction against the club should the case collapse.

The mood among select group referees, and their assistants, after the events of the last three days is one of disbelief that such havoc could be wreaked on a referee's career on the say-so of Premier League footballers. Clattenburg, accused of "inappropriate language", including a racial slur against John Obi Mikel, is now the subject of a police investigation.

Many referees feel they are all vulnerable to allegations that could easily have been made on a misunderstanding – or worse – and they believe as a whole there should be repercussions for Chelsea if the accusations against Clattenburg are without foundation.

Clattenburg himself is understood to be keen on a swift return to refereeing, although he accepted the decision that he is best left off the list for this weekend's fixtures. However, he does not want to spend too much time away and if the Football Association and police investigation drags on without any charges being pressed, he wants to referee again before the resolution of the case.

Somewhat ironically Clattenburg devotes much of his spare time to studying for a law degree. Originally an electrician, his law studies are well-known in the game where many of the top-level referees and assistants spend time together before matches. The seriousness of the case escalated yesterday when the Metropolitan Police activated an investigation on the basis of a complaint from Peter Herbert, chair of the Society of Black Lawyers. However, unlike with the John Terry-Anton Ferdinand case last year, the Met has not requested that the FA suspend its investigations until the end of the criminal inquiry, although it could yet do so.

Chelsea have conducted their own internal investigation by an independent barrister into the events of Sunday's game. The club believe that will be completed today. They were not prepared to go to the police with any complaint until that had been done.

The 37-year-old Clattenburg, who is being advised by Prospect, the union which represents referees and officials, is adamant that he did not utter a racial slur at Mikel or Juan Mata. He has not issued a public statement because he is yet to be formally accused of anything beyond Chelsea's original allegation of "inappropriate language".

The most serious allegation against Clattenburg is believed to be the Mikel incident that took place between his dismissal of Fernando Torres on 68 minutes and in the aftermath of his booking of the Nigerian for dissent eight minutes later. The Brazilians Ramires and David Luiz are understood to have alleged they heard an insult, which Mikel did not.

Manchester United and Chelsea meet again at Stamford Bridge tonight in the Capital One Cup with greater stewarding provisions in place to cope with a larger away crowd and a great deal riding on referee Lee Mason keeping the peace.

In a bid to restore some confidence in their officials, the referees' body PGMO (Professional Game Match Officials) have entrusted the two highest-profile televised Premier League games on Saturday – Manchester United v Arsenal and West Ham v Manchester City, to their leading referees, Mike Dean and Howard Webb.

Herbert, who made the complaint that triggered the investigation into Clattenburg, told The Independent that he had adopted a policy of "zero tolerance" and from now on would "almost certainly" be referring every race allegation in football to the police for a criminal inquiry.

Herbert said: "We got the impression that the industry hasn't got a grip on the problem. After speaking to some footballers and holding a seminar, we adopted a policy of zero tolerance that the people know there will be a swift and serious response."

Herbert said the four-match ban given to Terry as part of his punishment for racially abusing Anton Ferdinand, along with a £220,000 fine, was "laughable" and a "slap on the wrist".

He said that his organisation would push for police investigation into race allegations in football "until there is a proper strategy where the FA combats these matters effectively". Herbert said that he had not spoken to any of the players involved in the incident on Sunday.

It is unlikely that Mikel and Mata will feature in tonight's game. Oriol Romeu, a substitute on Sunday, said in an interview with Spanish radio that neither Mata nor Mikel heard the alleged slurs uttered by Clattenburg against them.

Chelsea to issue warning to fans

Chelsea will remind their supporters to behave amid a review of security arrangements ahead of tonight's Capital One Cup game with Manchester United. A repeat of Sunday's Premier League fixture will have increased scrutiny given recent events and the presence of twice as many United supporters.

Chelsea will issue a message in tonight's programme reminding fans of their responsibilities regarding the safety of fans and staff alike. On Sunday a Chelsea steward from the Matthew Harding stand had to be treated in hospital for a knee injury. It was sustained following movement in the crowd when Javier Hernandez scored United's winner. Missiles, including part of a seat, were thrown at United's players.

A Chelsea spokesman said last night that they will "keep security arrangements under continual review" but given Sunday's events, and the increased away fans, tighter measures are likely. Because tonight's game is Capital One Cup rather than Premier League there will be 6,000 United fans, twice as many as on Sunday, occupying the full Shed End upper and lower.

Jack Pitt-Brooke