In professional football, instances of players being banned for 'doping' offences are relatively rare. In November 2005, Abel Xavier became the first Premier League player to ever be banned for using performance enhancing drugs. He tested positive for the anabolic steroid, methandrostenolone, and was suspended for 18-months; a punishment which was reduced to 12-months after appeal. To date, no other Premier League player has been banned for intentionally using performance enhancing drugs. Kolo Toure was banned in 2011, after taking dietary tablets containing a prohibited substance. However, authorities eventually agreed that they were not intentionally taken to enhance his sporting prowess. Cases in other major leagues are also rare. Inter's Mohamed Kallon was banned for using nandrolone in 2003 and there have been several other cases scattered around Europe, but they are few and far between. This lack of positive tests has led many to conclude that football, unlike cycling, for example, is a clean sport. However, it would be incredibly naive to believe that football does not have a doping problem of its own. Many allegations have been made over the years, which suggest that the problem either exists beneath the radar or, even more worryingly, that authority figures within the game are fully aware of the offences and are choosing not to act. In 2007, German coach, Peter Neururer, alleged that doping had been rife in Germany in the late 1980s and early 1990s and accused several members of his own Schalke squad of using banned substances. At the forefront of his allegations was the substance Captagon, which he claimed almost every member of his playing squad used. Despite a denial from Schalke, Jens Lehmann, who was a young goalkeeper in Peter Neururer's squad, appeared to confirm the allegations. Meanwhile, former club doctors for Eintracht Braunschweig confessed to administering Captagon to players at that club throughout the 1970s and 1980s. Argentine legend Diego Maradona was involved in a doping scandal of his own in 1994, after testing positive for ephedrine. Maradona was sent home and the incident ended his international career. In 2011, however, Maradona announced that the entire squad had been using banned substances before a World Cup qualifying match with Australia. He also claimed that Julio Grondona, the head of Argentina's Football Association, was aware of the cheating. We were given a speedy coffee. They put something in the coffee and that's why we ran more. We took whatever the doctor gave us, he continued. Why weren't there any anti-doping controls in the match with Australia, if we had them in all the other games? They give you 10 anti-doping controls and only the match that decides whether Argentina will go to the United States or not, there is no anti-doping control. That's the cheat and Grondona knew about it. In England, the topic of performance enhancing drugs is something which has concerned Arsenal manager, Arsene Wenger, for many years now. Wenger has been an outspoken critic of the current system in place to test players, claiming it is insufficient. Honestly, I dont think we do enough, he said in February. It is very difficult for me to believe that you have 740 players in the World Cup and you come out with zero problems. Look at psychological tests that have been done on people who are at the top in all sports. When they ask them if they would take a product that would guarantee them a gold medal or a world championship, but mean that they died in the next five years, 50 per cent say yes. That is quite scary. That is how far people are ready to go to win in all sports. Sport is full of legends who are, in fact, cheats, he continued, before criticising current testing techniques. UEFAs doping control do not take blood, they only take urine. I have asked many times for that to change. Wenger's concerns with doping in football are nothing new either. He has spoken out several times over the years, claiming other managers share his views. In 2004, he said the following: We have had some players come to us at Arsenal from other clubs abroad and their red blood cell count has been abnormally high. An increased red blood cell count is consistent with EPO use. That kind of thing makes you wonder. There are clubs who dope their players without the players knowing, he said. The club might say that they were being injected with vitamins and the player would not necessarily know that it was something different. These claims are consistent with the testimony of Matias Almeyda, a former Argentina international. Almeyda said that during his time with Italian club, Parma, he was given an unidentified, but seemingly performance enhancing substance before matches. We were given an IV drip before games. They said it was a mixture of vitamins but before entering the field I was able to jump up as high as the ceiling. It may seem unbelievable that a club could get away with such obvious cheating. Yet testing for drugs in football is simply not comprehensive enough to stop it. In England, for example, during the 1999-00 season, testers only attended 32 matches over the course of the entire season. At those matches, only two players from each team were tested. Visits to training grounds are also rare and teams usually know about them in advance. Even then, only a few players are tested from the entire playing squad, including reserve and youth teams. A UK Sport's Independent Sampling Officer explained how simple it would be to get around this testing. If a club knows in advance we're coming, and the club suspects one of their players, they keep him off training and his name doesn't appear on the list I am given, he said. Of all the allegations of drug use in football, perhaps most troubling have been the claims made by Eufemiano Fuentes, the doctor arrested in 2006 as part of the Operation Puerto investigation into blood doping. Although the investigation focused primarily on cycling, Fuentes himself has admitted that he worked with athletes in various other sports, including football. I have done the same thing with other sports. I have given advice on treatments for football teams, athletes and tennis players, among other sports, he said. Independent allegations followed, including from a French newspaper, which claimed Fuentes had been associated with both FC Barcelona and Real Madrid. Despite this, authorities never went after the football players involved, even with Fuentes' insistence that he could identify all of them. Later, in 2010, he made an even more staggering claim: If I would talk, the Spanish football team would be stripped of the 2010 World Cup. The astonishing allegation should surely have led to a major investigation. Instead, earlier this year, a Spanish judge ordered that the blood bags, crucial evidence which could lead the investigation directly to the athletes involved, be destroyed. Almost immediately, rumours began to swirl suggesting a cover up, with cycling being held up as a sacrificial lamb in the investigation. With the recent Lance Armstrong scandal, the credibility of the sport is already damaged. However, investigating the others sports would open up a whole new can of worms, which those sports, and Spain as a country, could do without. However, sweeping the problem under the carpet should not be an option for football. As we have seen with the case of Lance Armstrong in cycling, these problems will eventually resurface. Any retrospective action taken could lead to the credibility of the entire sport being called into question. At present, it seems clear, judging from allegations made and from the sheer lack of testing that is carried out, that football has a long way to go before it can confidently declare itself to be a clean sport.