Emergency services were called to an accident at the corner of McGrath Road and Valewood Drive, Wyndham Vale this afternoon following reports a person on a pushbike had been hit by a vehicle.
A witness said that the rider did not have a helmet on and crossed the road without looking and was hit by what he described was a rigid tray concrete vehicle, or workers truck.
The witness stated that there were no skid marks and the vehicle did not beep the horn, it hit the rider and then stopped up the road.
Ambulance Victoria has advised that the 69-year-old man has been taken to the Royal Melbourne Hospital in what they believe to be a critical condition with upper-body injuries.
Westgate Highway Patrol officers are investigating the cause of the collision.
Any witnesses or anyone with dashcam footage is urged to contact Crime Stoppers on 1800 333 000 or file a confidential report online atwww.crimestoppersvic.com.au