Police are investigating whether fatigue might have contributed to a crash on Sunday on the Oxley Highway, south of Somerton.
At 2.15pm, emergency services were called to the site of the single car crash near Rushes Creek Road, where the 20-year-old male driver and his passenger were taken to Tamworth hospital for treatment on minor injuries.
The Westpac Rescue Helicopter was tasked to the scene but was called off when the vehicle occupants were taken to hospital by road ambulance.
According to Gunnedah Police Sergeant Mark Benson, the driver "veered onto the off side of the road, where they collided with a safety barrier over a creek".
The car then came back onto the road where it rolled, then landed and rested on its wheels.
The driver and passenger managed to free themselves from the vehicle, but according to Sergeant Benson the car was a write-off.
Investigations into the crash are continuing.