A man in his 40s who was airlifted to the Royal Melbourne Hospital in a critical condition following a crash in Ballan on Sunday night has had his condition improve.

A media spokesperson from the RMH told The Courier the man's condition has been downgraded from critical to serious.

EARLIER: 7am

A man has been flown to the Royal Melbourne Hospital in a critical condition after a crash on Sunday evening.

Emergency services were called to the Ballan-Daylesford Road in Ballan just after 7pm on Sunday to reports of a single-vehicle crash.

Fire crews from Gordon, Ballan and Myrniong turned out to the incident after reports the car may have been on fire following the crash.

Paramedics treated a man at the scene, aged in his 40s, for head injuries.

He was flown by air ambulance helicopter to Royal Melbourne Hospital in a critical condition.

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