Referees will clamp down on elbowing, dangerous tackles and diving to allow World Cup matches to flow, they said on Monday.

German referee Markus Merk appointed for the 2006 FIFA World Cup poses in Frankfurt.[Reuters]

Sometimes criticised for failing to adequately punish serious foul play, referees are under instructions from soccer's world governing body FIFA to ensure such problems do not spoil the tournament in Germany, which starts on June 9.

"Protecting skilful players is the main thing," English referee Graham Poll told reporters at a referees' open day.

"You want to see the best players playing the best football at the world's biggest sporting event. And referees have got to play their part in making sure they have the opportunity to do that."

The men with the whistles can go largely unnoticed for most of a match until they make a controversial decision and suddenly the centre of attention.

This happened a number of times at the 2002 World Cup when some referees were criticised for making highly contentious decisions that cost teams vital goals.

Referees have been given recordings of matches played by the teams they will be in charge of so they can become familiar with the different playing styles and formations.

BE PREPARED

"What is important is not to prejudge players or teams, not to go in preconditioning your mind to 'this is a very physical team' or 'this is a very cynical team'," said Poll.

"But we must be prepared, for example, so that if a team that gets a free kick in the defensive third always hits a long ball, there is no good you loitering around the defensive third saying: 'Can we have it on that blade of grass, please'."

Concerns over different players and teams interpreting rules such as offside in different ways is not fazing the referees.

"There are always going to be these discussions," said German referee Markus Merk. "You'll to have to trust us."

Trust in referees, though, has been questioned recently after a series of match-fixing scandals rocked domestic leagues in countries such as Germany, Italy and Czech Republic.

Italian referee Roberto Rosetti said the bribery scandals -- which have seen some referees jailed -- should have no impact on the World Cup and referees were not even thinking about them.

"The focus at this moment is only the tournament," he said.

In a show of determination to not allow such episodes to taint the World Cup, referees have signed a declaration promising that neither they nor their families will place bets on games.

"We need to be seen as above suspicion, above reproach, and every referee at this World Cup is happy to sign that," said Poll.

However, they know that whatever efforts they make to ensure fair play and no scandal, somebody inevitably complains.

"It's always the losers," said Merk.