A man has died in hospital weeks after an alleged road‑rage confrontation on the NSW South Coast.

The incident unfolded on Moona Creek Road at Vincentia about 1.25pm on March 17, when two people travelling in a Toyota Corolla, including a 79-year-old man, stopped to speak with the driver of a Ford Territory.

Police then allege the woman behind the wheel of the Ford allegedly assaulted the 79-year-old, causing him to fall and suffer a serious head injury.

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Paramedics treated him at the scene before he was airlifted to St George Hospital, where he remained in a critical condition.

On Monday, police were told that the 79‑year‑old had died in hospital, almost a month after the alleged assault.

In March, the 32-year-old woman was charged over the alleged assault and remains before the courts.

A report will be prepared for the coroner as detectives continue their investigation.