FA launches probe into referee complaint
Former Premier League referee Jeff Winter said Clattenburg would probably never be able to referee another match if media allegations he racially insulted Chelsea midfielder John Obi Mikel and verbally abused Spaniard Juan Mata are true.
The Metropolitan Police has confirmed it has now received a complaint about the referee and that it will be working alongside Chelsea to determine what action, if any, will be taken.
While Clattenburg has made no public comment on the case, Sky Sports reported he has strongly denied using any inappropriate language and is "mortified" by the allegations.
The FA said on Monday it had begun investigations into the alleged incidents that occurred during United's 3-2 win at Stamford Bridge where Clattenburg sent off home players Branislav Ivanovic and Fernando Torres.
United won the game with a goal scored by Javier Hernandez who came back from an offside position before firing in from close range. The infringement was not spotted by the linesman and Clattenburg allowed the goal to stand.
He will not be officiating at any Premier League matches this weekend after the Professional Game Match Officials Board (PGMO), which manages top English referees, said on Monday he was being stood down given the "intense level of scrutiny".
Former Premier League referee Winter told British media: "If a match official has used racist language, he won't be getting a four or eight-match ban, it'll probably be the end of his career - but that is indeed if he did say anything."
Chelsea captain John Terry is serving a four-match ban for racially abusing Queens Park Rangers defender Anton Ferdinand last year while Liverpool's Luis Suarez had an eight-match ban last term for racially abusing Manchester United's Patrice Evra.
Chelsea host United again in Wednesday's League Cup fourth round match and although teams often rest leading players in the competition, the clash will take on extra significance given the controversy surrounding Sunday's Premier League encounter.
Although the club would not name the players Clattenburg is alleged to have used inappropriate language towards or of what nature the remarks were, a spokesman refused to deny that Nigerian Obi Mikel had visited the referee's room after the game.
Mikel was booked for dissent during the second half.
Spaniard Mata has also been identified in the media as the other player insulted by Clattenburg with As newspaper in Spain reporting, from unnamed sources, that the referee called him "an idiot Spaniard".
After the match, a club spokesman told reporters: "We have lodged a complaint to the Premier League match delegate with regards to inappropriate language used by the referee and directed at two of our players in two separate incidents.
"The match delegate will pass the complaint to the Football Association. We will make no further comment at this time."
An investigation is also being carried by the Metropolitan Police into how a Stamford Bridge steward was injured following Hernandez's winner.