The 33-year-old man thought he had sealed a deal on mobile marketplace app Carousell to sell his Rolex watch for $31,800.
At a Jurong void deck in the wee hours of Saturday, the buyer put on the watch and handed Mr Jonathan Lian an envelope filled with what Mr Lian thought was the agreed amount.
But he got the shock of his life when he discovered that it was stuffed full of fast-food restaurant fliers.
Mr Lian, who works in the IT industry, told The New Paper: "The moment our eyes met, he knew that he had been discovered.
"He ran off with the watch on his hand and we gave chase."
With the help of his cousin who had accompanied him to the meeting, Mr Lian was able to catch the cheat.
The deal was struck on Friday at Block 822, Jurong West Street 81.
Mr Lian said that the man, who gave his name as Andy Ong, contacted him via online marketplace Carousell around 9.30 that night.
They had agreed to meet at the void deck of the block at 11.30pm.
Before he left his home, Mr Lian's father had cautioned him against making a deal involving the expensive watch so late at night, but Mr Lian ignored the warning.
"He was nagging but I didn't think that anything would go wrong. I even challenged him and said, 'I hope I get robbed,'" said Mr Lian, who has been buying and selling watches as a hobby for the past eight years.
After chatting for about two hours, the man told Mr Lian and that he would buy the watch but had to go back to his flat to get the money.
After waiting for about 40 minutes, Mr Lian and his cousin grew suspicious and called the man, who told them that he had gone to the nearby Pioneer Mall to withdraw money as he was $2,000 short.
Mr Lian said: "When he came back, he asked to see the watch again but this time I stood right next to him.
"He wore the watch and said he liked it and handed me the envelope. That's when he ran."
Mr Lian and his cousin gave chase for about two minutes and managed to pin the robber down a couple of blocks away from the original meeting point. Mr Lian also called the police.
He said a woman, who claimed to be a passer-by, walked up to them and told them not to hit the man.
But after the police arrived, he overheard the police saying the woman was the cheat's wife.
Mr Lian said the police also told him that the man was wanted for other cases of theft.
The police said that they received a call at 3.32am on Saturday, asking for assistance at Block 819, Jurong West Street 81.
On arriving, they established that a case of cheating had occurred.
A 34-year-old man and a 27-year-old woman were arrested.
Investigations are ongoing.
This article was first published on February 2, 2016.
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