Man's head pinned between truck and pillar

A man is fighting for his life in a Melbourne hospital after his head became pinned between his truck and a concrete pillar.

Police say the man was washing his semi-trailer at a Laverton North truck wash on Wednesday afternoon when his rig began rolling forward.

The man tried to stop the truck but his head became wedged as the door ran up against the pillar.

The man was freed by paramedics and taken to the Royal Melbourne Hospital in a critical condition.