His son claims his father’s two hearing aids were knocked out during the incident and his prescription glasses smashed, and that he had to crawl to his vehicle after being attacked.

Police say they are investigating an “alleged assault”.

“He’s just an absolute mess,” the man’s son said. “He’s visibly very battered and bruised.

“He’s been pretty much banged about and was nearly knocked out cold.”

The businessman – who is the director and shareholder of multiple companies – is about 30 years younger than the pensioner. The vehicle he was driving is registered in a relative’s name and worth about $430,000 new.

Photos of the 73-year-old’s injuries show numerous scratches and bruises. A doctor’s report says his symptoms included “concussion: forgetfulness, difficulty finding words [and] amnesia of the incident”.

The pensioner has been told to rest “cognitively and physically”, limit screen time and not drive a vehicle for up to six weeks while he recovers, and may need to be treated at a concussion clinic.

He also suffered “severe pain” from a likely partial tear to his hamstring and “large hematoma”, along with a shoulder injury which will require six weeks’ treatment and referral to physiotherapy, the report notes.

However, the businessman told the Herald the pensioner was the one at fault, after the elderly man’s Kia Sportage allegedly tried to “run me off the road”.

The Herald visited the businessman last week at his $2 million-plus Ponsonby home. He would not come to the door but spoke to a reporter via an intercom.

He refused to comment in detail on the incident, but said if anyone was the victim, it was him.

“I was assaulted by this gentleman,” he alleged.

Asked if he suffered any injuries, the businessman replied: “I will leave this with the police right now. But yes, there’s the possibility that I suffered injuries.”

He would not comment further, telling the Herald its line of questioning was “quite rude” and “bordering on harassment”.

‘I did give him the one finger salute’

In a written statement to police – obtained by the Herald – the pensioner said he was driving home north on SH1 between Oteha Valley Rd and Silverdale when he noticed the luxury sports car “up my bum” in the right-hand lane, trying to overtake.

The man claimed he was about to move into the left lane to let the sports car pass when he noticed it had cut to his left-hand side, with the driver waving and gesticulating.

“Me thinking, ‘What a clown’, I did give him the one finger salute,” the man wrote.

Next, the sports car allegedly pulled in front of the elderly man’s Kia and slowed to about 60km/h, the man wrote.

He then felt a “bump” as the two vehicles collided before he exited the motorway at Millwater, but realised the sports car was following him.

The man said he decided to pull over before reaching his home as he “did not want confrontation on my doorstep”.

He exited his car and walked towards the sports car saying, “You are so wrong” when the driver allegedly “charged at me” and “started to punch me left and right blows to the head”.

The sports car driver allegedly pulled the older man’s sweatshirt over his head and threw him to the ground “where he continued to rain down blows on my head and body”, the statement alleges.

“Stunned and disorientated”, the man got to his feet, pulled his sweatshirt back down from head and “staggered around”.

He recalls saying, “You smashed my effing glasses” before the sports car driver allegedly launched a second attack.

“He once again threw me to the ground … hitting me and I think some kicks or stomping.

“When it stopped I was completely disorientated and when I tried to get to my feet my left leg would not support me and I was staggering and close to passing out.”

‘My dad’s 73 and this guy is a lot younger’

A police spokeswoman said officers were investigating an alleged assault in Silverdale about 3.30pm on August 11.

Police received a report of two vehicles involved in a minor collision, which resulted in both drivers pulling over and exiting their vehicles.

“An altercation has occurred between occupants of both vehicles. Both people left the scene immediately afterwards, but later one presented to a medical centre with moderate injuries.

“Police have identified and spoken with both parties involved and are determining the next steps.”

The son said while his father shouldn’t have got out of his vehicle, the incident should never have boiled over into violence.

The pensioner was still “traumatised” mentally and physically, he said.

“My dad’s 73 and this guy is a lot younger.”

Following the altercation, it’s believed the businessman contacted police to report that he had been assaulted.

The son said police then arrived at his father’s house but after seeing his injuries asked him to make a formal statement, which included photographing his bruises and scrapes. Police were also trying to obtain CCTV footage.

The son said another motorist had also witnessed the incident and contacted police independently.

He was upset that his father had been hurt over something as trivial as a motoring incident.

“To have this happen to your own family is bad. I don’t want this happening to anyone else.”

Lane Nichols is deputy head of news and a senior journalist for the New Zealand Herald with more than 20 years’ experience in the industry.