The man, in his 40s, was trapped in the wreckage for more than 90 minutes after his car left the Tylden-Woodend Rd and hit a tree just before 8pm.

CFA and SES were called to the scene to cut him free.

Ambulance Victoria spokesman John Mullen said the man suffered head, chest, abdominal and lower-leg injuries in the crash.

The man was placed in an induced coma before he was flown to Melbourne in a critical condition.

He remains in The Alfred hospital.

Meanwhile, police have not released the name of a 24-year-old Smythesdale man killed in a ute rollover on Sunday.

The man was discovered in his vehicle at 7am Sunday morning, but police believe the accident may have happened as early as 3am.

Police believe the man lost control in the gravel on Smythesdale-Ross Creek Rd and ploughed into a small tree and several bushes before flipping over.

Police said the man had spent the evening at a friend's house prior to the accident and was married.