An $8,000 Facebook Marketplace deal went bad on Long Island, with a man who was selling a Rolex watch jumping onto the hood of the thief's car in a quixotic attempt to keep from being robbed.

"I was not going to roll over and let this man take it ... without a fight," Steve Mauro, the seller, told The Associated Press on Sunday.

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The 43-year-old had arranged to sell the Rolex, purchased just days prior, on Friday in front of his home in Massapequa Park. A would-be buyer showed up and asked Mauro to approach for the money. But instead of handing over the cash, the thief locked his doors and started speeding away, Nassau County Police said.

Officers coincidentally patrolling the area saw a gray Honda SUV launch into reverse and knock Mauro over. Mauro jumped on the hood, but was thrown off as the driver fled with the luxury watch, police said. Mauro was treated at the scene for minor cuts to his hand, elbow and knee.

Describing himself as a seasoned Facebook Marketplace seller, Mauro said he didn't expect foul play.

"I can always sniff out a scammer from the very beginning and this guy didn’t come across that way at all," said Mauro, who ran to the nearby officers as soon as he was tossed from the SUV. "I started screaming ‘Go get him, he has my Rolex!’"

But the thief was already gone.

Police are promising anonymity to anyone who comes forward with information about the theft to Nassau County Crime Stoppers.