FIFA has warned South Africans not to get involved in illegal betting syndicates, mostly from Asia, that are expected to descend on the country en masse in the run-up to the World Cup.
FIFA says the multibillion-dollar industry is controlled by organised criminals who engage in loan-sharking and use intimidation and violence to collect debts.
And while illegal betting is not as big in South Africa as it is in Europe and the Far East, SA Football Association boss Kirsten Nematandani has warned local referees and premier league teams to be vigilant.
He said Safa was already investigating several claims of match-fixing in the PSL and had sent all premier league referees for lie-detector tests. A report was due soon, he said.
"I can't say much more about the claims but there are a number of allegations being investigated. We have to stay vigilant and continue to watch out for signs of match-fixing."
FIFA president Sepp Blatter will hold an extraordinary general meeting in Cape Town on Wednesday. An ongoing investigation into match-fixing in Europe will be discussed.
Blatter said at the opening of the Soccerex business conference in Johannesburg on Monday that the economic crisis had resulted in some resorting to match-fixing.
"There is cheating, violence, doping, illegal betting and many other problems in the game," said Blatter.
FIFA had asked Early Warning System (EWS) in Switzerland to keep Asian crime syndicates and other gambling mafias around the world from fixing matches, he said.
EWS started monitoring the preliminary competition of the World Cup in 2007 and is now monitoring all FIFA competitions.
EWS spokesman Wolfgang Feldner said Africa's sports betting share on the world sports betting market was about one percent.
"Based on the estimation that the world-wide turnover for sports betting is over $300 billion (R2 219 billion) a year, we know there is an important share in illegal betting in this amount, particularly in the Asian market," he said.
"We cannot make statements or estimations about the illegal sports-betting market in South Africa in particular, but are monitoring the world-wide market," he said.
Interpol secretary-general Ronald Noble said in a 2008 report on illegal betting and organised crime that 430 people had been arrested and 272 underground gambling dens - handling $650m in illegal bets - had been shut down.
He said gambling on soccer matches might seem as harmless as placing a small bet on your favourite team but these illegal operations were often controlled by organised criminals who frequently engaged in loan-sharking and used intimidation and violence to collect debts.
"If that doesn't work, they force their desperate, indebted victims into drug smuggling, and the family members of victims into prostitution," said Noble.
"One must remember that organised crime never loses money in gambling operations - one way or another, they make a profit."
From 2003 to 2005, police in Hong Kong had seized more than $10m in cash and betting slips related to illegal soccer gambling.
Noble said that while it was difficult to determine the exact amount of money involved in the match-fixing, European football governing body UEFA had claimed that an overseas syndicate had made $5-million on one championship match alone in July 2007.