In the first incident just after 11am, a woman believed to be in her 40s was travelling north from Invercargill to Dunedin when she lost control of her gold Mitsubishi hatchback on a right-hand bend, 5km north of Balclutha.
A witness to the incident said the vehicle had ''completely missed'' the corner, before leaving the highway at the intersection with Stony Creek Rd.
The car glanced off a power pole before coming to rest on its side in a paddock.
No other vehicles were involved.
Rescue services were quickly on the scene to cut the victim free, he said.
Police said the woman was taken to Clutha Health First in Balclutha for treatment to minor injuries.
The second crash had occurred when a female driver of a small black vehicle lost control on a corner near the Crichton railway overbridge, about 9km northwest of the earlier incident, about 3pm.
The woman had been travelling north from Balclutha to her home in Milton when the accident occurred, and was also taken to Clutha Health First in Balclutha for treatment to minor injuries.
Alcohol was not thought to have been a factor in either crash, police said.
