The referees' union today pledged their “full support” to Mark Clattenburg after Chelsea accused him of using “inappropriate language” towards John Obi Mikel and Juan Mata.
Clattenburg was this afternoon waiting to hear whether the Football Association would launch an investigation into allegations he made comments towards Mikel and Mata, which are understood to have been interpreted as racist, during the Blues' Barclays Premier League defeat to Manchester United yesterday.
Chelsea last night made a formal complaint to the match delegate, whose report was expected to arrive at FA headquarters today.
Clattenburg, 37, was given the full backing of Prospect, who said in a statement: "Prospect is committed to helping to eradicate racism in football and in society generally.
"In the context of that commitment, Prospect is offering full support to Mark Clattenburg in relation to the allegations made against him.
"It is now important that the allegations are fully investigated through the proper process as quickly as possible.
"We will be making no further comment at this stage."
Mikel's agent and Chelsea also refused to comment further on the matter today but the club did confirm they had decided against holding a press conference tomorrow to preview Wednesday night's Capital One Cup clash against United.
The Red Devils were similarly taciturn, although it is understood they were unaware today whether any of their players heard Clattenburg's allegedly "inappropriate language" and could act as witnesses.
It is unclear how many Chelsea players witnessed what transpired but almost certain to be called upon should there be an investigation are Clattenburg's assistants and fourth official yesterday, with each connected by a microphone and earpiece throughout the game.
Former Premier League referee Graham Poll told BBC Radio Five Live: "A referee's microphone is on open. Everything he says is heard by two assistants.
"So if Mark said something, the assistants would have heard it."
He added: "If a comment of a racial nature was made, I think it should be reported and I think assistant referees will report it because there's no place for it."
Jeff Winter, who retired as a referee shortly before Clattenburg became a member of the top flight's Select Group, claimed the official's career was doomed if he was proven to have used racist language towards a player.
Luis Suarez and John Terry received respective eight and four-match suspensions this year for racially abusing Patrice Evra and Anton Ferdinand.
But Winter, who refereed for over 25 years, felt Clattenburg would be forced from the game if found guilty.
"If a match official has used racial insults or language to a player then he's for the high jump," Winter said.
"He won't be getting a four-match or an eight-match ban, it'll probably be the end of his career, but that is if indeed he did say anything."
Clattenburg was unavailable for comment directly, but the body that represents referees, Professional Game Match Officials (PGMO), released a statement last night in which it said the referee has promised to co-operate with any investigation.
Winter felt he would be stood down in the meantime.
"I feel it very unlikely that Mark Clattenburg would be allowed to referee until it's dealt with so we certainly don't want this going on for weeks and months," he said.
Winter found it ironic a referee had been accused of using inappropriate language given officials were subjected to abuse from players and fans at almost every match.
He added: "Initially, it is insulting words and I must admit I smiled at that because we watch football matches every week of the year hearing players use insulting words to referees and then somebody takes umbrage when somebody allegedly says something back. But I just hope this can be cleared.
"It's slightly ironic that players dish it out left right and centre and then if - and there is a massive if - something has been said back - and we're not talking about racial here, we're talking about like for like - then I don't think anybody's got a right to complain.
"I'm not saying referees should do it, but there seems to be one law for one set of people and one law for another, but this inference that racial language has been used is very, very serious."
Anti-racism group Kick It Out refused to comment on the unfolding story this morning.