"Standard practice is that, if there's no ambulances available in the immediate vicinity, they will send the closest available resource. Our understanding is that, in the Hughes incident, that crew was from Summer Hill," he said. Phillip Hughes. Credit:Getty Images Summer Hill is about 10 kilometres from the SCG. The first triple-0 call from the SCG on Tuesday was made at 2.29pm, six minutes after Hughes was struck on the head by a ball during a Sheffield Shield match. That ambulance did not arrive until 2.52pm - 23 minutes after the initial call.

While the union did not have access to official Ambulance Service of NSW data, Mr Wilson said the 23-minute delay indicated that the vehicle was travelling from some distance away. Those at the SCG made a second triple-0 call at 2.37pm. In response to that call, an ambulance was sent from nearby Prince of Wales Hospital at Randwick. It arrived at 2.44pm, seven minutes after the call. Mr Wilson said the most likely scenario on Tuesday afternoon was that, in the minutes between the first and second triple-0 calls, an ambulance had managed to offload a patient or an emergency call had been cancelled, freeing up a crew. Hughes, 25, was taken to St Vincent's Hospital where he underwent emergency surgery, but he died on Thursday afternoon without regaining consciousness. Mr Wilson said ambulance crews taking a patient to hospital had to remain with that patient until hospital staff could take over their care.

However, if a hospital was too busy or under-resourced, the delay for ambulance crews, known as trolley block, could be considerable. Trolley block was not isolated and was often a source of frustration for paramedics, he said. Mr Wilson said that, following Tuesday's accident, he had "heard no criticism from the crews on the road about NSW Ambulance management or the call centre staff". "What we seem to be faced with is a resourcing issue in NSW Health," he said. "The big thing here is that trolley block leads to delays in ambulance responses. It's not rocket science.

"It really is symptomatic of a wider issue within the health system." Mr Wilson said that, since Tuesday's incident, paramedics had contacted the association to report that they had experienced similar problems in their local areas, but, because the person involved was not high profile, the public did not become aware of it. "We extend our condolences to the Hughes family and his colleagues. It's always a sad thing when incidents like this happen," Mr Wilson said. "It is disappointing it takes an incident like this to bring these problems to the public's attention, but it's only through public pressure that these problems are going to be addressed." A spokeswoman for NSW Health Minister Jillian Skinner said that, following the cricketer's death on Thursday, she would not be commenting on the association's claims on Friday.