LATEST: A WARRNAMBOOL man was killed in a crash near Inverleigh last night.
The man, believed to be in his 30s, lost control of his Ford sedan in Murgheboluc, west of Geelong.
Police said the car was travelling east along the Hamilton Highway about 8.30pm.
It is believed the car crossed over to the other side of the road and collided with a west-bound Hyundai.
The three occupants of the Hyundai, a man, woman and a nine-year-old boy, all from Mt Gambier, were airlifted to The Alfred hospital suffering non-life threatening injuries.
Paramedics treated the driver of the Ford but he died at the scene.
Senior Constable John Volf from Bacchus Marsh police, said the Warrnambool man was on his way to Melbourne to pick up a truck for work.
He said the cause of the crash was being investigated.
"Somehow he has ended up on the wrong side of the road, sliding on the passenger side of the car," he said.
"He may have over-corrected slightly."
Police will prepare a report for the Coroner.