Tan Seet Eng has been described to the world as a crime lord, the head of an international match-fixing syndicate, a schemer who manipulated the results of 150 football matches across four continents.

But who is this man who has allegedly turned the world of football upside down, an elusive Singaporean whose alias, Dan Tan, is on every match-fixing report filed by Interpol and Europol officers, and on the wanted list of the Italian police?

Reporters have found him impossible to reach. He had moved out of his Rivervale Crest condominium unit in Sengkang to a HDB flat in an undisclosed location, and most friends lost contact with him after he disconnected his home and mobile phone numbers last year - incidentally a few months after he was accused by the Italian authorities of being the chief of a global match-fixing syndicate.

Had he something to hide?

Double lives

But friends say the man they know is anything but the hardened criminal the European authorities have made him out to be.

"He is just your average Joe," a friend, who spoke on condition of anonymity, told The Sunday Times. "He is a very jovial and happy-go-lucky guy. Our nickname for him is 'Ah Blur' because he always seems so unaffected by anything going on around him."

But their average Joe is leading a more-than-average life.

According to people who know the plump 48-year-old, Tan came from humble beginnings. A secondary school dropout, he is known to be street smart and is said to be a salaried employee in a local company.

But that is not his only source of income, according to those who know him. He is said to have a keen eye for investments, building a prolific portfolio in the share market over the years.

Tan is also known to be an avid gambler, punting several thousands of dollars a time on horse-racing and football. He frequents the casinos and is described by friends as a high-roller. In total, his bets run into the millions per year.

"He likes a punt. And he likes to win. He hates losing - in anything," said a source who has known him for four years but has only met him occasionally.

Gambling landed Tan in jail in the early 1990s. He served time for less than a year after falling foul of the law for being an illegal horse-racing and football bookmaker.

He was also said to have fled Singapore in 1994 after losing more than $1.5 million betting on that year's World Cup.

But he returned after his creditors agreed to let him pay off his debt in instalments.

Low profile

Tan is believed to have bounced back quickly from this setback: enough to be commuting in a BMW 7 Series saloon and living in his private apartment that he shared with his wife - a Chinese national - and a young son.

He also travelled frequently to cities all over the world.

Apart from that, he displays no trappings of wealth.

"Dan is very low profile. He neither wears jewellery nor does he even have an expensive watch. Whenever we meet, usually at neighbourhood coffee shops, he is wearing a T-shirt and jeans," said a source.

Those who know him say Tan does not drink alcohol or smoke, and spends most of his free time watching television at home and monitoring the stock market on his laptop.

And, as peculiar as this may sound, he does not even watch football.

"Dan is not a football fan and watches football only occasionally," said the source. "He punts on matches, but he is very relaxed. Some punters will be checking live score websites every other minute but he is very indifferent."

Dealing with fixers

How Tan made his money, nobody is sure. But gambling is an obvious avenue. And it is his fierce desire to win that probably saw him hook up with match-fixers.

Match-fixers who have secured a fix usually hawk their betting tips to any punter who is willing to pay for them.

With fees going as high as $20,000 per game, fixers will share the pre-determined results with their clients.

"Dan gambles heavily and, in the process, may have been approached by match-fixers offering tips for cash," said a source.

"And he may have paid lots of money for these tips to increase his chances of winning. But to accuse him of actively planning and manipulating results all over the world is too far-fetched."

Convicted Singaporean match-fixer Wilson Raj Perumal is said to be one of those who supplied betting tips to Tan.

They used to be business partners, said someone who knows both men.

Perumal, who jumped bail from Singapore in 2010 and fled the country using bogus travel documents, had persuaded Tan to invest in his now-defunct company Football Four U (later known as Exclusive Sports), set up in 2009, which dealt with sports events promotion.

"Through this company, Wilson Raj wanted to buy a share of Finnish football club Tampere United and Tan agreed to come up with the money, around 300,000 euros (S$498,000)," said someone with knowledge of the deal.

"But when Tan realised that Wilson Raj planned to use the club ownership to manipulate the team's results, he got worried and withdrew his investment."

A grudge

That left Perumal in limbo and the pair are said to have fallen out after that.

Said the source: "Wilson Raj was arrested in Finland shortly after that episode and he probably believed Dan betrayed him and therefore still bears a grudge.

"That may explain why he told the Finnish and Italian investigators that Dan is the ringleader of a match-fixing syndicate."

To this day, Perumal insists that Tan instigated a certain Joseph Tan Xie to tip off the Finnish police that eventually led to his arrest. But Tan's friends whom The Sunday Times spoke to say they have never heard of Joseph Tan Xie.

And they do not believe that Tan would betray Perumal.

"Dan is very loyal to his friends and is always ready to give people a second chance," said a source.

"His soft-heartedness is also his biggest weakness."

Whether Tan betrayed Wilson Raj, and whether he really is the mastermind of a match-fixing syndicate, remains to be seen.

But a source said: "Dan's name was first brought up by the Italian authorities in 2011. Two years on, he remains a free man.

"If all they said is true, they would have arrested him long ago.

"So what does that tell you? They can't nail him because they do not have evidence of his alleged crimes. He is clean."

Or at least perceived to be.