A police spokesman said officers were called to the two-car collision on Lee Stream-Outram Rd (State Highway 87) about noon on Saturday.
One car was a silver Toyota Corolla hatchback, while the other was a white Porsche Cayman 718 GT4 RS.
A photo of the crash indicates the cars collided head-on.
A St John spokeswoman said an ambulance took one person to Dunedin Hospital with serious injuries.
In an update today, Senior Sergeant Anthony Bond, of Dunedin, said a 65-year-old man — who was driving the Toyota, a rental — appeared to have had a medical event.
His car crossed the centre line into the path of the oncoming Porsche, Snr Sgt Bond said.
It appeared the man's condition was improving today, Snr Sgt Bond said.
Media reports indicate that New Zealand deliveries of the Cayman were expected to start in the third quarter of this year.
According to Porsche’s website, prices for the 368kW sports car start at $291,000.
The Otago Daily Times understands the driver of the Porsche was uninjured, but the car — one of only two of its kind in the South Island — will likely be written off.
One lane was temporarily blocked and two tow trucks were called to the incident, police said.
Inquiries are continuing.
