Brimbank Highway Patrol officers are appealing to anyone who has dashcam footage of a crash on the Western Ring Road in St Albans last night.
Emergency services responded to reports of a blue Hyundai i30 leaving the road, driving down an embankment and crashing into a creek bed about 9pm.
A female passenger, aged in her 20s and from Tarneit, was taken to hospital with serious injuries.
The male driver, a 20-year-old Tarneit man, was taken to hospital with a minor injury and will be spoken to by investigators.
The investigation into the circumstances surrounding the crash remains ongoing.
Anyone who witnessed the incident, has dashcam footage or any other information that could assist police is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au.