A man stabbed outside a pub was taken to hospital in a fire engine because the area's three ambulances were busy.
Mr Baker was taken to hospital from this pub in a fire engine
An investigation has been launched by the Welsh Ambulance Service, which said it was taking it very seriously.
The fire engine took John Baker, 48, nine miles (14km) from Maesteg to the Princess of Wales Hospital, Bridgend, where he is in a stable condition.
A 36-year-old man has been charged with attempted murder and will appear before Bridgend magistrates on Tuesday.
Mr Baker was injured outside the King Alfred pub in Maesteg at 0050 GMT on Sunday.
The ambulance service said the three ambulances for the area were busy on other calls at the time.
A spokesman said an ambulance was sent from the Royal Glamorgan Hospital in Llantrisant, 20 miles (32km) away, but it was stood down when it was 10 minutes away because the fire engine had already left.
Martyn Harris, of Maesteg fire crew, said: "He had lost a lot of blood and he was lapsing in and out of consciousness.
"So it was imperative that we got him to hospital as soon as possible."
Mr Baker's family later visited the station to offer their thanks to the fire crew.
Maesteg station commander Wynne Matthews, said: "They were obviously quite distressed. They seemed to be coping quite well, given the gravity of what happened."
An ambulance service spokesman said: "The three vehicles on duty in the Maesteg area were already committed.
"The nearest available ambulance was at the Royal Glamorgan Hospital and this was dispatched but was stood down when police responders informed control that they would convey the patient in a fire brigade vehicle.
"At that stage the ambulance was within 10 minutes of the scene but was stood down."
The spokesman added: "We take this matter very seriously and the trust has launched a detailed investigation to establish exactly what happened."
All three of the area's ambulances were busy on other calls
It went on: "Two recent reports from the auditor-general and Healthcare Inspectorate Wales identified long-standing and deep-seated problems within the ambulance service and, while there are no instant or easy solutions, we are working extremely hard to put things right."
The Welsh Assembly Government said it was committed to the modernisation of the Welsh Ambulance Service and to demonstrate this had provided £71m for new ambulances and communication systems.
The ambulance service has suffered turbulent times in the past year with changes at the top in management, claims of crisis and response targets being missed.
Earlier this month a temporary plea was issued for people living in Cardiff and the Vale of Glamorgan to only dial 999 in life-threatening situations.
The state of "special emergency" was downgraded later the same day after call levels returned to normal.
However, chief executive Alan Murray has said a promised £55m radio system and the unveiling of the first of a fleet of 119 emergency vehicles marked the trust's determination to improve the service.
South Wales Police have appealed for witnesses to the incident outside the King Alfred in Maesteg.