Sydney driver charged as struck pedestrian fights for life

A driver has been charged after a pedestrian was hit and left fighting for life in Sydney's south west.

A 57-year-old man was found with serious head injuries on the Hume Highway in Yagoona after he was allegedly hit by a Toyota Yaris before 4am today.

The man was taken to Liverpool Hospital where he remains in a critical condition.

The 56-year-old hatchback driver was taken to Bankstown Hospital for mandatory testing as investigators assessed the scene of the crash.

He was arrested about 12.30 today and charged with a string of offences including dangerous driving occasioning bodily harm and running a red light.

The Cabramatta man has been granted conditional bail and is expected to appear in Bankstown Local Court on April 29.