Dash-cam footage captures the moment the 75-year-old was forced to stop his car beneath the railway bridge on Roberts Road in Acocks Green, Birmingham, before being threatened.
Three men with an imitation firearm and a large kitchen knife forced him to get out of his Ford S-Max before driving off in the vehicle.
They managed to drive a matter of yards before stalling the car, and were unable to restart the engine.
The fearless pensioner confronted the thieves and was assaulted and pushed to the floor, but refused to hand over the car keys.
After hearing the commotion, local residents came out to help. The trio, unable to start the car without the key, ran off.
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