Ambulance Victoria said a man in his 20s was flown to the Royal Melbourne Hospital in a critical condition with upper body injuries.
The driver has been freed from the car that crashed into a creek at Yarraberb.
An SES spokesperson said a multi-agency taskforce performed a high-angle rescue to free the man from the wreckage.
"Ambulance Victoria will take him shortly," the spokesperson said. "The teams were working together to extricate the patient owing to the nature of the site.
"It is a steep embankment adjacent to the creek bed. The car was a bit unstable on embankment."
An Ambulance Victoria spokesperson said paramedics are still on the scene with one male patient expected to be airlifted to hospital shortly in a critical condition.
SES crews are working to remove a driver who is in a critical condition after a crash at Yarraberb.
Emergency services were called to the scene on Sebastian Road, near the intersection of Marong-Serpentine Road, at 11.22am following reports of a car crashing into a creek.
It is believed the vehicle ran off the road and crashed down an embankment before stopping in the bottom of the creek.
Ambulance Victoria confirmed an air ambulance was en route to the scene.
"Paramedics are on the scene and the air ambulance has been dispatched for one patient who appears to be in a critical condition," an AV spokesperson said.
Victoria Police units have closed Sebastian Road.
An SES spokesperson said Marong and Bendigo units are on scene to extract the driver from the vehicle.
"Volunteers appear to be performing high angle rescue," the spokesperson said. "They are also liaising with other emergency services including an air ambulance."
A CFA spokesperson said two trucks were on scene alongside SES.
"Upon arrival, it was determined one occupant of the vehicle is trapped and will require extrication," the CFA spokesperson said.
The incident is not yet under control.
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