A man has been charged after shocking footage surfaced, showing the moment he allegedly revved a chainsaw after a road-rage brawl unfolded in the middle of a busy Fairfield road.

The dashcam video, taken just after 4.40pm on Tuesday, shows a white Jeep entering an intersection on The Horsley Drive where traffic is backed up and trying to make a right turn.

The driver is forced to stop in front of a line of traffic. Within moments, a shirtless man can suddenly be seen sprinting towards the Jeep from the back of the line of cars.

The video shows the man running to the driver's window and swinging at him. The driver can be seen trying to fight him off from inside the vehicle, before he gets out and throws a water bottle, and a few punches, at the attacker.