The attack, which took place at the car supermarket's Darlaston branch in Staffordshire, happened after a customer requested a test drive in an Audi A3.
During the drive the assailant told the salesman he had a knife and pulled into a lay-by where two accomplices forced him from the car and left him at the roadside as the gang made their getaway.
The salesman, who wishes to remain anonymous, told the Express & Star newspaper that there was nothing suspicious about the man when he arrived at the car supermarket.
“He told me he was looking for a family car then he spotted the Audi and asked to take it for a test drive. We had just driven around the corner when he pulled over and reversed into a lay-by and I noticed two men sitting in the front of a green Rover.”
The salesman said he was then forced from the car as the two waiting men pulled him from the Audi.
He added: “The man put the window down and said to the pair, ‘this is the car, this is the car'. Then he told me to get out of the car, that he had a knife and the others grabbed me and pulled me out. They left me at the side of the road and they sped off.”
West Midlands Police are investigating the incident and have called for witnesses to assist with their enquiries.
Officials said they were
looking for an Asian man
in his late twenties or early thirties.
As Motor Trader went to press no arrests had been made and the stolen Audi had not been recovered.