Football is rightly known as the beautiful game but there are occasions when it passes over into more of an x-rated status.
From time to time something happens during a match that goes down in infamy as an act of violence rather than footballing style.
Here are five examples of incidents in the World Cup that will live long in the memory for all the wrong reasons?
The Battle of Santiago (1962)
Chile, as hosts of the 1962 World Cup, were drawn in the same group as two-times winners Italy and even before the two teams met in Santiago there was tension between the countries.
An earthquake in 1960 had disrupted Chile's preparations for the tournament but journalists in Italy used this against the country and spoke in a less-than-friendly way about the hosts.
Local newspapers in Chile then used these articles and angered readers, so much so that the two writers concerned had to leave the country before the tournament because they feared for their own safety. Added to that, an Argentinean journalist was mistaken for an Italian and beaten up in a Santiago bar.
A foul just 12 seconds after the kick-off set the tone for 90 minutes of remarkable scenes. Italy's Giorgio Ferrini was sent off with just 12 minutes on the clock but refused to leave the field and was dragged off by policemen. His offence had been a foul on Honorino Landa, who later threw a punch of his own, but wasn't dismissed.
English referee Ken Aston had one almighty task on his hands to keep control and he let a punch by Chile's Leonel Sanchez on Mario David go, but when David responded by kicking Sanchez in the head in the 41st minute the Italian was given his marching orders.
Then it all erupted with Sanchez breaking the nose of Italy's Humberto Maschio. The violence continued and three more times police had to intervene to separate the players.
Chile won 2-0, and when highlights reached the BBC they were prefaced by David Coleman describing the footage as, 'the most stupid, appalling, disgusting and disgraceful exhibition of football, possibly in the history of the game'.
Harald Schumacher (1982)
It is a wonder incidents like this don't happen more often with goalkeepers rushing out to meet opposing players but the outcome of this one was so brutal that the question of malice has remained over the head of goalkeeper Harald Schumacher.
The 1982 World Cup semi-final between West Germany and France was a real thriller but has gone down in history for a collision between Schumacher and France's Patrick Battiston.
Battiston was chasing down a long ball towards the edge of the German penalty area when out rushed Schumacher and he charged straight into the Frenchman, rendering him instantly unconscious on the pitch.
Battiston's shot went wide but he had no idea as he lay flat out, missing teeth too, and his injuries at the time were so severe that he later slipped into a coma.
No foul was given at the time so Schumacher went unpunished but thankfully Battiston went on to make a full recovery and the goalkeeper has since apologised to his opponent, a gesture which has been accepted by Battiston.
Benjamin Massing (1990)
If the Harald Schumacher incident could be described as questionable in terms of malice, there could be no question whatsoever surrounding Benjamin Massing's challenge on Claudio Cannigia in the final stages of the 1990 World Cup opener.
Cameroon, in their first World Cup, were a goal up and a man down against defending champions Argentina as Cannigia broke forward in search of an equaliser for his side.
He had beaten a couple of Africans before being forced wide where he was hunted down by Massing, who was already on a yellow card but showed no concern over that as he dived in with a challenge that could best be described as 'wild'.
The ball had gone as Cannigia was chopped down in full flight and sent sprawling to the floor. Massing, who had already accepted his fate as he got up, actually lost a boot in the tackle such was the force he used when he leapt in. Amazingly he only collected a second yellow card rather than a straight red that the incident was surely worthy of.
Zinedine Zidane (2006)
Zinedine Zidane's World Cup legacy is one of the ultimate high and the ultimate low following his star turn in 1998 and his ignominious exit from football eight years later.
He scored twice in the 1998 final as France beat Brazil to win the World Cup in their own country and by 2006 the career of one of the game's modern greats was coming to an end as the midfielder had already confirmed his retirement following the tournament in Germany.
Many observers reckoned he single-handedly got France to the final that year and having received the Golden Ball as the player of the tournament prior to the final, it looked like a fairytale ending was on the way seven minutes in as he scored with an impudent penalty to put France ahead.
Marco Materazzi equalised on 19 minutes and the pair were to come head to head - or rather head to chest - 10 minutes from the end of extra-time.
TV viewers were unsure of what had happened when footage showed Materazzi floored just outside his own penalty area but it soon became apparent that Zidane was involved one way or another and referee Horacio Elizondo showed a red card to the French skipper.
Zidane left the field with no real protest and the sight of him walking past the World Cup at the side of the pitch was one probably the 2006 tournament's most iconic image.
Replays soon showed that Zidane and Materazzi had been walking up the pitch when suddenly Zidane turned back to his opponent, walked towards him and drove his head into the defender's chest with force and anger.
There were various versions of events as to what had sparked Zidane's ire but it later transpired that Materazzi had made an insulting comment.
Materazzi went on to score in the penalty shoot-out as Italy won the tournament before he was handed a two-match ban and a fine by FIFA for his part in the incident. Zidane was given a three-match suspension but as he was retiring anyway he served three days of community service on FIFA projects.
Nigel de Jong (2010)
Howard Webb must have thought his luck was out as the 2010 World Cup Final between Holland and Spain progressed.
The English official flashed his yellow card with staggering regularity throughout the 90 minutes and subsequent extra-time as he did his best to keep all 22 players on the pitch.
His book came out for the fifth time with just 28 minutes played as he flashed it at Manchester City's Dutch midfielder Nigel de Jong following a challenge on Spain's Xabi Alonso.
But that challenge had been with de Jong off the floor and his studs showing as he drove his foot into Alonso's chest with force as the pair tussled for a bouncing ball. Observers said it was a definite red card and felt that the Dutchman was very lucky to escape with only a caution.
Webb later admitted that his view of the incident had been restricted at the time but on reviewing it again he felt that it was worthy of a red card.
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