Greensborough Highway Patrol officers are investigating a hit-run collision in outer suburban Wollert early today.
Two bike riders were travelling in the bicycle lane along Yann Drive about 12.50am, when one was struck by a vehicle.
The cyclist, a 46-year-old man, was taken to hospital with serious injuries.
The second was not physically injured.
The driver of the vehicle, believed to be a black utility with a tray, did not stop at the scene to render assistance.
Attending officers located a side mirror on the road, believed to have come off the left side of the utility during the collision.
The investigation remains ongoing.
Anyone who witnessed the incident, with footage or information is urged to contact Crime Stoppers on 1800 333 000 or via www.crimestoppersvic.com.au.
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