Police are appealing for a truck driver who may have witnessed a crash at Prospect to come forward.
Just before 6.45am (Tuesday, July 28 2015), a white Nissan Pulsar sedan was stopped at an intersection on the Prospect Highway and waiting to turn right into Stoddart Street.
A truck travelling in the opposite direction stopped at the intersection to let the Nissan proceed.
Police have been told as the Nissan turned into Stoddart Street, it collided with a motorcyclist travelling in the opposite direction.
The motorcyclist, a 20-year-old man, was treated at the scene by Ambulance Paramedics and taken to Westmead Hospital suffering serious injuries.
The driver of the Nissan, a 32-year-old man, was uninjured.
Officers attached to Blacktown Local Area Command attended and commenced investigating the incident.
As they continue their inquiries, police would like to speak to any witnesses who have not yet come forward.
In particular, police would like to speak to the truck driver who stopped to allow the Nissan to turn into Stoddart Street to come forward and contact Blacktown Police via Crime Stoppers.
Update your news preferences and get the latest news delivered to your inbox.