Emergency services were at the scene near the intersection of Robertson Rd and SH1 near Waiwera South about 3.10pm.
Constable Andy Denny, of Clinton, who was at the scene of the crash, said the driver of the car had gone too wide at the corner and overcorrected, causing the car to roll and end upside down in a ditch.
A woman, who sustained a minor hand injury, and a man managed to climb out of the car and were transported to a Balclutha hospital by a St John ambulance.
Invercargill woman Danette Pikia, one of the first at the scene, said she was driving and saw the rolled car in the ditch.
''I pulled over and started to direct traffic,'' Ms Pikia said.
The man and woman were already getting out of the car when she arrived.
''They looked a bit shocked.
''I think they were extremely lucky to be relatively unharmed.''
