Mann said not only did Martin hit Macpherson with the back of the axe while he was fighting with another man on the ground but he then turned it so he was smashing him with the blade.
She argued after he issued the fatal blow to Macpherson's right leg, hitting a significant artery which killed him, he then continued to hit him, only stopping when someone else took the axe off him.
"Having administered that blow, Mr Martin did not stop there. He did not stop until he was stopped."
But defence lawyer Phillip Morgan told the jury the critical issue for them was to work out what happened that "shocking" night.
Morgan warned the jury that some witnesses that would be called to give evidence "were not telling the truth", or would not give accurate accounts, and it was up to the jury to determine what happened.
Morgan said his client was defending both charges.
He said Martin argued he was not guilty of assault causing injury to Fisher-Williams, because it was accidental and he had actually been trying to protect him and stop the fight between the pair.
"Rydell Martin struck intending to hit the deceased with an axe, missed and accidentally hit his cousin."
Morgan did not deny Martin had assaulted Macpherson but said there was no intent to murder him.
He said at this stage it was not "in defence of his cousin" who had run off at this point but an unlawful act and he was "guilty of manslaughter, not murder".
It would be up to the jury to draw their own conclusion about why Martin assaulted him and what was going through the defendant's mind at the time, he said.
Witness 'feels like a piece of s***'
The first witness on the trial told the court how he feels "like a piece of s***" for grabbing a vacuum pipe and wood-splitting axe before checking if his friend was in trouble.
Jonothan Shand, who admitted his memory was hazy at times, had been drinking with his girlfriend Sonia Macpherson, her brother Phillip Macpherson and another man, Shane Matangi, at their Robert St property in Pukemiro.
Not long after Macpherson had left the house, Shand said he heard yelling from down the road and was worried his friend was in trouble as there had been tension building between him and others in the town.
Shand said he went to grab his keys to his ute but couldn't find them so picked up an axe and vacuum pipe to use in "self defence".
"It was a stupid decision. I feel like a piece of s***."
At the same time, his girlfriend Sonia Macpherson hopped in her Toyota Yaris towards where the noise was coming from on Joseph St.
When he arrived on foot a group of men, including the accused Martin and another man, were yelling abuse at Sonia in her car.
Shand had seen the group earlier in the night and recalled Martin drinking a jar of "gin and juice" and said they were singing and rapping and blocking the road with their vehicle.
The same group then asked him what he was doing with an axe, to which he replied that was just looking out for his bro and didn't want any trouble.
He said he was then "flipped over a fence" by Martin, resulting in him knocking his head, with things becoming "pretty hazy after that".
Shand said he was trying to defuse the situation and was still holding the axe but the pipe had been taken off him by Fisher-Williams.
Martin then put his arm around him "like a mate" while he noticed someone was hitting and scratching the Yaris with the pipe.
He was then told Macpherson – who had since appeared – was having a "one out" or a fight with Hanuere Fisher-Williams.
When he noticed Alazay Fisher-Williams had also joined in, he called out that it wasn't fair.
"I said this isn't a one out and this was when I was attacked."
He said Martin had the axe up around his neck and he managed to wriggle under it before "gapping it".
He fell and grazed his knees as he ran back to the Robert Ave house to get help.
Within minutes he had grabbed Sonia's car with the plan to run the men who were fighting Macpherson over "because he was outnumbered".
But when he arrived he found a lifeless Macpherson lying on the ground and blood was pouring out of him.
He then picked him up and bundled him up in the back of the hatchback.
When they got back to the house, he called to the other occupants to help and they tied a hoodie around his leg while waiting for emergency services to arrive.
'Macpherson swore as he ran towards group'
A childhood friend of Macpherson's had told the court they had spoken about whether the van full of younger men who they had bumped into on Joseph St and who included the accused Martin, had been responsible for stealing a chainsaw from Shand's ute.
Shane Matangi was with Shand and Macpherson when Macpherson asked the group if they had stolen it when they were blocked in the middle of the street earlier in the evening.
There was a bit of an argument between him and the other group about it and Macpherson later told his friends, "I bet it was them."
Shane Matangi who was called as the second witness said they then went back to Macpherson's Robert Ave home. The trio had a few drinks, a few laughs but also "got a bit angry" about the chainsaw being stolen.
Later in the night, Matangi said he had "just a beer in his hand" and a small blade in his pocket while Shand had an axe and vacuum pipe when they went jogging towards Joseph St where they thought they had heard Macpherson yelling from.
The pair had told each other they should leave the weapons at home – but didn't.
As they were jogging towards Joseph St they bumped into two of the men they had spoken with earlier in the night and asked them if they knew where Macpherson was.
The men said they didn't, but challenged Shand about why he had an axe.
Matangi said he then pulled the axe off Shand and threw it into the back window of a car driven by Sonia Macpherson.
His story differed from Shand's and claimed Shand was unarmed when Martin flipped him over the fence.
The pipe had already been taken off him and had been used by Martin who had hit and scratched the car before chasing Matangi down the road with it, Matangi said.
"He (Martin) was screaming all this s*** like I'm going to f*** you up ...
"There was a lot of swearing and angriness."
After running away from Martin, Matangi bumped into Macpherson.
"He came running down the hill from somewhere," he said.
"He was quite angry and was running down trying to see what had happened to his little sister and aunty.
"He said 'you little buggers, what the hell do you think you are doing?'"
Matangi then ran off as more people came out onto the street, including a couple of young women.
The trial is set out for two weeks before Justice Mary Peters, with 22 witnesses expected to be called.
The trial continues.
