England warned: stop swearing

England's players have been warned by the controversial Brazilian referee who will take charge of Saturday's World Cup opener against the United States that he is learning English swear words in order to know whether he is being abused by players.

The referee Carlos Simon and his two assistants have revealed that they have been learning from a list of 20 obscenities while they have been training at the centre for the tournament's referees in Pretoria. It could have a direct effect on Wayne Rooney, a habitual abuser of referees and linesmen, who has already been warned by a South African referee that he could find himself dismissed for bad language.

Simon already has a reputation in Brazil for making bizarre decisions and at what will probably be his last tournament after three World Cup finals he is regarded by many in his own country as a loose cannon. His assistants Altemir Hausmann and Roberto Braatz, both Brazilian, said this week that they had become more familiar with the abuse they could potentially receive from England and US players.

Hausmann told the Brazilian broadcaster Globo Sporte that he expected players to swear but that the trio wanted to know the severity of the language being used against them. He said: "We have to learn what kind of words the players say. All players swear and we know we will hear a few 'son of a...'"

His fellow assistant Braatz said that it was only English that they were studying. He said: "We can't do this in 11 different languages but at least we have to know the swear words in English."

Last night Fifa said that it had not instructed the Brazilian officials to learn English swear words. The governing body demands that all referees at the tournament have a good level of English but do not specify anything about bad language. There has been no move to encourage referees and their assistants to learn abusive terms in any language and it raises the possibility that English players could find themselves at a disadvantage.

Rooney was heavily criticised by the South African referee Jeff Selogilwe who took charge of England's friendly against Platinum Stars on Monday for swearing at him during the match, raising the possibility that England's striker could be marked out for special treatment.

Fifa have already prevented the English referee Howard Webb, who will take charge of Spain's first game against Switzerland, from speaking to the England players about the potential offences that referees are cracking down against. In that instance the governing body's "integrity unit" ruled that it could give the England team an unfair advantage.

The World Cup referees and their assistants are only assigned matches a week ahead and are kept in complete isolation at their base in Pretoria. They are expected to attend debriefings for every single game played at the World Cup and security guards are posted outside their hotel to stop any visitors. Fifa regards them as potential targets for match-fixing.

Simon's decisions in domestic Brazilian football have proved so erratic at times that the Rio de Janeiro club Flamengo petitioned Fifa unsuccessfully to have him thrown out the tournament after he missed a blatant penalty award for them. He previously took charge of England's 2002 World Cup tie against Sweden.