The man and his partner, who had just arrived back at their Dunaff Place home around 12.05am, discovered another man they didn't know outside their house.
Counties Manukau detective senior sergeant Darrell Harpur said a fight took place between the two men and the victim was shot.
He was taken to Middlemore Hospital and was now in a stable condition.
Harpur said police were treating the matter seriously and were still working to establish exactly what had occurred at the address.
Several neighbours said a group of about five young people were drinking in a car on a construction site adjoining the street earlier on Sunday evening.
But a mother of 10 who lives a few doors down from the house where the shooting occurred said she also saw an older man, who she thought was in his 30s, outside her house about 11pm, before the shooting.
"How I found out was my niece and nephew were at the shops and came home and he goes to my niece, 'What are you doing here?' " the mother said.
"I walked out and he just looked at me. He looked suspicious, I knew he wasn't from the street. Then I came inside and called the cops.
"He looked like he was 30-something. He had a beard. He had a cap on. He had a singlet, pants, and he had a top around his shoulder."
She did not see a gun.
The mother said police interviewed her but did not tell her that someone had been shot, and she only found out about the shooting from the media.
"They didn't tell us there was a shooting, or at least give us a warning that there was a guy out on the street with a gun so we can lock our windows," she said.
Neighbours said another house in the short street was robbed about two years ago and a man was seriously injured. A young Filipino family who had been renting the house moved out the next day.
Cars have also been broken into on the street several times.
Police warned members of the public to call 111 immediately if they saw any suspicious behaviour or were in a situation where they felt unsafe.
