Mr Slater said it was the man who attacked him. He told the court he parked outside the man's drive in January 2010 to work next door.
Mr Slater said he heard a woman yelling at him to move but he refused to as there was "plenty of room". He later found the man trying to move his van, then found him fitting a wheel clamp.
The accused man's lawyer, Simon Lance, asked Mr Slater if he had pushed his client or kicked him. He replied: "I never touched him. I went to stand up and next thing I knew, I'm flat on my back." Mr Slater said the man threw "left and rights" at his head.
Neighbour Jacqueline Woods told the court she heard raised voices, and saw the man straddling Mr Slater, who was on his back, with his forearm across his throat.
When Mrs Woods threatened to call police, the man replied that his wife already had and that Mr Slater had assaulted him.
The accused man's wife told the court she saw Mr Slater kick and punch her husband while her husband knelt down to fit the clamp.
Mr Slater was taken to hospital days later and was diagnosed with bleeding on his brain.
In his opening statement, Mr Lance said the case was "a little unusual" and his client was not charged until 15 months after the incident.
Later on, Mr Lance said Mr Slater's denial that he had touched his client was "a lie".
"What did the police officer say who interviewed Mr Slater on the day? 'Neil admitted to pushing [the man]'."
He said Mr Slater had grazes on his elbows, a small cut to his ear and a bit of blood in his mouth.
"That's not a description of someone who has been beaten up."
He added that while Mr Slater said he was punched to the ground, Mrs Woods never saw this.
