The man was taken to Middlemore Hospital where he remained in a critical but stable condition.
The victim's car was driven from the scene and dumped nearby, where it was later found by police.
Mrs Mathews said police enquiries were continuing, but help from the public was needed.
"Police are interested in receiving any information about the victim's 1996 black BMW 528i sedan acting suspiciously around the Manurewa area between 2.30am and 4.30am," she said.
"Further information is not available until we are able to speak to the victim who is still in hospital with serious injuries.
"We are currently following up on CCTV footage from the area which will hopefully provide us with some more information on the incident."