Mario Tionko, 55, lived at the address outside where the man was attacked.
He told the Herald that while he was having dinner someone knocked on his door and told him a pizza delivery man was lying on the ground outside his house.
He ran out and saw the man lying on the ground in a pool of blood.
Tionko said the delivery man was semi-conscious and told him he was delivering it to a different address.
The concerned resident went to the address where the order was intended to discover the resident had not placed an order.
Ula Faakomiti, 25, said no one was home at the time except for a sister who was sleeping. No pizza order had been placed by anyone at the property.
Another Kelman Rd resident Louisa Mauauri said she passed by soon after the attack and noticed the neighbouring family and a policeman tending to the injured man as blood poured from his body.
"They were standing over there with the guy who was bashed.
"I just saw a pool of blood on the footpath," said the Kelston resident.
The shocking ordeal had left everyone shaken.
"It's just a bit frightening because this has never happened in our street."
Detective Sergeant Kelly Farrant said those behind the attack took off with $20 and the pizza.
She said it was not known how many people were involved in the brutal assault. The weapon used to strike the unwitting worker was also a mystery.
"Police staff are absolutely disgusted by this offending. An innocent member of our community was just doing his job, when he was struck over the head and left there unconscious. This could have been far more serious had a member of the public not found the victim and called for help," she said.
Police were appealing for anyone who witnessed any suspicious behaviour in the area to call police.
The injured man was using his silver coloured Subaru Impreza at the time of the attack.
"If you saw anything then please contact police as soon as possible. Even if it is something minor, we want to hear about it," said Farrant.
"We want to hold whoever is responsible for this crime to account and place them before the courts.
"People have a right to go to work and do their job safely without being violently assaulted. It is simply not good enough and the Waitakere community will not accept it."
Anyone with information was asked to called Detective John Schieb at Henderson Police Station on 839 0600 or Crimestoppers anonymously on 0800 555 111.
