A driver is seriously injured in hospital — and likely facing charges once police speak with him — after an alleged high-speed chase and three-car crash on South Australia’s Fleurieu Peninsula.

Police said a white Holden Commodore sedan was detected at 146km/h in a 60km/h zone on Port Elliot Rd in the beachside town of Middleton, between Victor Harbor and Goolwa, about 9pm on Wednesday.

Another police patrol then spotted the same car doing a U-turn in Goolwa and turned on their lights and sirens, directing the driver to stop.

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However, police say the driver did not stop and officers gave chase, terminating the pursuit when the Commodore entered a 100km/h zone on Port Elliot Rd heading back toward Middleton.

Soon after police discovered a three-car crash involving the same Commodore at the intersection of Port Elliot Rd and Boettcher Rd, Middleton.

A 41-year-old man, allegedly the driver of the Commodore, was taken to hospital with serious injuries.

A 65-year-old Goolwa South woman was also injured when her Land Rover rolled and was taken to hospital for treatment.

The third driver, a 35-year-old Goolwa North man whose vehicle was clipped, was not injured.

All three vehicles were towed away and debris cleared before the road could reopen.

Investigations into the crash are continuing and police said the Commodore driver was expected to be charged with multiple driving offences.