"When I hit the car, that driver was full of rage.
"He opened his door, came up to me, I opened the window and he shook his fist through the window."
"The passenger who pulled off the other guy went outside and said to him, 'the driver has just been assaulted, so simmer down'."
At the time, 15 passengers were on board for the trip from Downtown to Otahuhu via Glen Innes.
Mr Pillay took yesterday off to let swelling on the left side of his face heal and he plans a medical check today before returning to work.
He said the attack came as a surprise.
A minute earlier the passenger - "a big grey-haired man of 50 to 60"- had demanded to be let out and was told that he could at the next bus stop.
"Otherwise, the bus would have held up the traffic - we had been diverted around road works from the normal route."
Mr Pillay said he could smell alcohol on the man's breath and he was drinking from a can.
Auckland City Police attended the incident but a spokeswoman said Mr Pillay's assailant had disappeared by the time they arrived and police would like to hear from anyone who saw the incident or who knew the man's name.
Mr Pillay said that a month ago a passenger had punched him on the jaw.
"I picked him up in the Link Bus on Queen St and he refused to pay the fare.
"Some guys caught him and threw him off."
Mr Pillay said he had driven buses for two years after service as a driver of a total mobility taxi.
Previously, he had driven taxis on Friday and Saturday nights and had been punched in the head and face.
As a result, he had installed a CCTV camera on the dashboard to film inside the cab.
An Auckland Transport spokesman said it had not heard about the assault on Mr Pillay but was concerned.
"We will be seeking a full report from the Police and operator NZ Bus."
Auckland Tramways Union president Gary Froggatt said the city's bus drivers get frequently abused for frustrating delays because of traffic snarl ups.
"Once a week, we get reports of an assault on a driver or one being spat on, out of 1100 drivers.
"It's totally unacceptable for passengers to take it out on the drivers because it's not their fault."
NZ Bus did not respond to requests for comment.