A man has been arrested over the killing of an insect expert in the suburb of Blockhouse Bay.
A homicide investigation was opened after Stephen Thorpe, 54, was found stabbed on Saturday morning in Rathlin Street, in the West Auckland suburb.
A man had been charged with murder and would be appearing in court on Thursday, police said.
Police were not seeking anyone else, Detective Inspector Glenn Baldwin said.
"I know there will be questions about why this happened to Stephen, and our team have the important task now of piecing together all the information so the judicial process can be carried out."
Police had searched a nearby property on Exminster Street overnight as part of the probe, he said.
On the day he died he had been working at his office in the tennis club.
He then went outside, where a violent struggle took place, ending in Thorpe receiving stabbed wounds before dying at the scene, police earlier said.
A staff member working at the club witnessed Thorpe during the struggle and went to get a phone to call for help, police said.
Thorpe was a keen entomologist who had been working at an office beneath the Blockhouse Bay Tennis Club for several years.
A friend of his, Jacqui Knight, told RNZ he was very knowledgeable about anything to do with insects, which were his passion.
"He spent seven days a week at the office - he just loved it. He was a loner who kept to himself most of the time and wouldn't hurt a fly. It's just so tragic this has happened."
One of his colleagues, Gary Andrew, from the Whau River Catchment Trust, told the Herald Thorpe was a gentle quiet scientist.
"He was a small, slightly built, well-spoken, educated, gentle guy who would just never hurt a fly. It just felt incredibly sad that something has happened like this. It's so pointless."
Thorpe had no close relatives living in New Zealand, Knight said, and had originally been from Australia. Police said they had been in contact with his immediate family in Australia.