Just before 11am on Saturday, 19 June police were called to a two vehicle collision on Tremona Road, near to the hospital.
A yellow Mazda MX-5 had been in collision with a white VW Golf.
The driver of the Mazda, a 73-year-old man from Gillingham, was taken to Southampton General Hospital for treatment for his injuries. Sadly, he died in hospital on Monday, 21 June.
His next of kin have been informed and are being supported by specialist officers.
If you witnessed the collision, have any dash cam footage, or would like to talk to police about this incident, please contact 101 quoting reference 44210239245.