The tirade against the assistant referee was easily picked up by the pitch-side microphone and broadcast across the world: 'Are you blind or what? I didn't [expletive] touch it!' The speaker, disputing a relatively meaningless throw-in, was from a northern European country normally known for its placid nature and good manners. But in the English Premier League, all politesse goes out the window when it comes to the now-ingrained culture of putting pressure on match officials. It was one of the hundreds of similar incidents during a weekend when Mark Clattenburg was at the centre of a controversy that saw him allow Nani's goal for Manchester United after Tottenham goalkeeper Heurelho Gomes had mistakenly assumed that a free kick had been awarded because of a hand ball. Some observers were outraged by Clattenburg's perceived error in judgment for allowing play to continue and then his failure to give a clear signal to the obviously confused Gomes. But the fact that so little was made of the outrageous behaviour of two Manchester United players on the edges of the melee underlines just how tolerant the Premier League is of referee intimidation, especially from its most famous clubs. Seconds before he handled the ball, Nani appeared to have been brought down in the box by Spurs' Younes Kaboul but when Clattenburg didn't award a penalty, he was grabbed by Red Devils' veteran Paul Scholes. Later, when Clattenburg consulted with his assistant Simon Beck, whose flag had been raised as the ball went into the net, United captain Rio Ferdinand was in the face of both men, even though the referee had just shooed away a bunch of Tottenham players. And when Clattenburg decided that Nani's goal should stand, Ferdinand appeared to give the linesman a final piece of his mind before getting ready for kick-off. It was alarming to see the actions of Scholes and Ferdinand go unpunished, while Luka Modric received a yellow card for joining in the protests of his Spurs teammates. Just like during the previous weekend when Andre Marriner astonishingly declined to give Manchester United's Gary Neville a second yellow card after a reckless challenge on Stoke's Matthew Etherington in the 42nd minute, there seems to be one rule for Manchester United and another for the lesser sides. The fact that Alex Ferguson substituted his veteran fullback at half-time indicates the manager realised what a generous decision his team had received. Another notorious incident involving Manchester United saw Andy D'Urso chased around by a pack of players led by Roy Keane after a penalty was awarded to visiting Middlesbrough at Old Trafford in January 2000. Former international referee Dave Roberts, who is now a referee coach, says that England's biggest clubs are among the worst culprits when it comes to abusing referees. 'Manchester United are as bad as any team in the Premier League, Chelsea too,' the Middlesbrough-based Roberts said. 'Ref baiting has been a part of the game for some time and to many it's now just accepted. The reason players do it is to put pressure on officials to get them to change their minds, or so they feel they have to favour the seemingly wronged side at a later point in the game.' Two years ago, the Football Association introduced its 'Respect' programme to address the unacceptable behaviour on and off the pitch, which had seen thousands of referees quit the sport every year. As well as players, it reached out to coaches and spectators - including parents who can be so vocal and aggressive on the sidelines of junior matches. But when it comes to controlling the multi-millionaires of the Premier League, respect apparently goes out the window. One can understand the reaction of bitterly disappointed manager Harry Redknapp, who blasted Clattenburg in post-match interviews for his strange ruling that effectively killed off any chance that Spurs had of getting something out of an important game. But for players to man-handle referees or to get up close and personal while they consult with their assistants is intolerable. Anyone who has played both soccer and rugby at even amateur level can attest to the differences when it comes to referees. In rugby, it's all about calling them 'sir' (or 'miss') and having only the captain question their rulings. In the round-ball game, everyone seems to angrily chirp away at the whistle-blower with the most colourful of phrases. Roberts, who has worked as an assistant alongside Clattenburg in England's minor professional leagues, agrees that a 'zero tolerance' policy is the best way forward. 'That's the only way to get rid of referee baiting but you'll see a large increase in yellow and red cards - do we really want that?' he asked. 'A couple of seasons ago, the FA was used by Fifa to test a 'rugby-like' method of punishing dissent where a referee would issue a yellow card and advance the ball 10 yards. I thought it was a great idea but unfortunately the experiment was not taken forward by Fifa and was shelved.' With more than 20 TV cameras covering some high-profile games, officiating errors are now seen from multiple angles and are often replayed over and over again, with referees ridiculed, lambasted and even vilified. But for anyone who touches a referee under any circumstance, it must be a straight red card - retrospective if necessary - while an automatic yellow is appropriate for a player who butts in to a conference between match officials. Just as every competitive game needs a ball, it also requires the man or woman in the middle. So why don't we better protect referees, even if it means bruising the egos of a few misbehaving players along the way?