A paramedic told a court how an assembly member with a head injury punched him after he came to his aid.
Montgomeryshire AM Mick Bates, 62, was found drunk and slumped in a restaurant in January, Cardiff Magistrates' Court heard.
Paramedic Carl Jones said Mr Bates struck him as he attempted to treat the politician for a head injury.
Mr Bates denies three counts of common assault and public order breaches. The trial continues.
Magistrates heard how police and ambulance staff were called to Charleston's Steakhouse in Caroline Street, Cardiff, in the early hours of 20 January.
On arrival they were approached by Craig Williams, a friend of Mr Bates, who claimed the assembly member had been injured after suffering an assault.
The court was told police went inside and found a clearly drunken Mr Bates lying semi-conscious on the restaurant's entry staircase, bleeding from a head wound.
Mr Williams is said to have then described a man he claimed pushed Mr Bates down the stairs and who he said was still inside.
Police carried out a thorough search of the premises but only found its three members of staff and a dog.
The court was told that in the meantime, paramedics had arrived.
Cardiff paramedic Carl Jones, giving evidence, said Mr Bates flailed his arms around and was aggressive.
He said: "I said calm down sir, we are here to help you. You have got a cut on your head and we need to get it assessed."
He said Mr Bates was "abusive and somewhat aggressive. There was a strong smell of intoxicants and a clear reluctance to co-operate with both myself and Darren" (Noble), his crew mate.
He said the assembly member swore and shouted that he was not going to hospital, and they were unable to examine him.
It was decided to carry him to the ambulance in a wheelchair but when it was brought the AM refused to stand, he said.
"We found it was safer to take him down on his buttocks one step at a time," he said.
Mr Bates was strapped into a wheelchair inside an ambulance ready to be taken to hospital for assessment when he punched the paramedic in the chest, the court heard.
Mr Jones said he was preparing to take Mr Bates' blood pressure when he felt a tug on his clothing and a "sharp blow" to his chest.
"It happened so quickly, to be honest, all I felt was a tug and a dull thud but it was a heavy blow which did wind me for a short period of time, " Mr Jones added.
He said he immediately left the ambulance and reported what had happened to a police officer.
The officer spoke with Mr Bates who did not react but showed signs he had calmed down, the court heard.
The assembly member has been suspended from the Welsh Liberal Democrats pending the outcome of the case.