Skull fractured in Vic roadside attack

A 51-year-old man trying to fix his housemate's car on a Victorian roadside has been beaten by two men who fractured his skull, dragged him unconscious into a ditch and left him for dead.

The man had driven to the scene of the attack to help his female friend, who was stranded in Yellingbo, just outside Melbourne's outer northeast.

She then walked into the bushes to go to the toilet while he tried fixing the car late on Tuesday afternoon.

Police say the woman, 44, heard screaming and yelling.

She ran to flag down a passing driver, who took her to Belgrave, where she called police.

Other motorists also reported seeing two men beat another man with a pole and drag his body into a ditch along Macclesfield Road.

Paramedics found the man unconscious and took him to hospital, where he remains in a critical but stable condition.

The broken down car was also missing and has since been reported stolen.

Detective Senior Sergeant Alan Price says it's a bizarre attack and crucial that police track down the passing driver who drove the woman to seek help.

"We need to get to the bottom of it," he said.

"It's an unwarranted attack that's caused significant injuries."

He said the woman went by the name "Meredith" and was driving a beige Ford Territory.