The man and woman both managed to climb out of the wreckage but the man later collapsed with a suspected back injury and had to be carried out by firefighters.

The couple's car rolled on Brindabella Road at Piccadilly Circus about 7.30am.

The woman remained at the scene but the man walked about 200 metres to find a mobile phone signal to raise the alarm.

Both were stabilised by intensive care paramedics before being taken to the Canberra Hospital in a stable condition for further medical assessment.