When St John had arrived there was "no urgency", he said.
"The ambulance comes down the road and just pulled up slowly. It was hopeless. For that time of morning, it's pretty quiet around town," he said. "To me, it's not good enough for a city of this size. I don't understand it.
"His head was on the road where the cars go by and if no one had stopped and cared for at least half an hour, I mean who is responsible for that?" he said.
St John assistant director of operations Lee Brooks confirmed two ambulances called to Shortland St yesterday morning had been diverted.
The first call to St John was made at 7.23am, but the incident was assessed as neither serious nor life-threatening.
Shortly after 7.27am, it was upgraded to urgent or potentially serious.
An ambulance was sent from Pitt St at 7.26am, but at 7.29am it was diverted to a "potentially life-threatening or time-critical incident".
At 7.30am, a second ambulance from Auckland City Hospital was sent to the scene. That ambulance was also diverted.
A third ambulance was dispatched from Mt Roskill at 7.32am and arrived at the scene at 7.52am — 29 minutes after the original call.
The man was taken to Auckland Hospital in a moderate condition.
"Our three call-receiving centres across New Zealand answer in the region of 1200 to 1300 emergency 111 calls per day," said Brooks.
"Every call is important to us as we strive to provide the best possible care for all patients.
"To achieve this we use an internationally recognised system to prioritise calls so we can respond in a way that ensures appropriate care, assistance and resource for every patient, as was the case with this incident."
The St John service aims to get to the most life-threatening 111 calls within eight minutes — a target it has struggled to hit.
And in the past 11 months, the service had trialled a new system in which nurses were stationed at 111 emergency call centres to answer "non-urgent" calls, St John said.
In the 11 months since the trial started until last month, St John had received 117,574 emergency calls, of which 22,150 were urgent.
That had freed up an extra 1.5 ambulances on the road 24 hours a day, seven days a week.