Crown prosecutor Andrew Britton told the jury in his opening statement that Gripp stabbed Pawa six times, with the knife puncturing Pawa's heart, diaphragm and liver.
He said Pawa and some of his family members were drinking in the centre of town on the day of the attack, and generally creating a "nuisance".
His relatives had earlier gotten into a fight with a person in Mongrel Mob attire, which police had to break up.
Later in the afternoon, Gripp and his cousin drove into town and confronted Pawa's group, with Gripp's cousin throwing the first punch, Britton said.
Pawa, who had been further away, came running when he saw his brothers getting into a fight.
Gripp got in and out of his car several times, at one point trying to drive away as Pawa and the others attacked it.
They eventually let go of the car as Gripp accelerated away. But the fight resumed when Gripp stopped the car a short distance down the street and got out again, this time carrying a knife.
He said words to the effect of "do you want to get stabbed" before stabbing Pawa six times, Britton said.
The fight was then broken up by an off-duty police sergeant, with members of both groups fleeing in various directions.
Gripp and his cousin fled in the car, with witnesses reporting seeing the driver of the car laughing as it disappeared.
Pawa collapsed in the Te Rauparaha Park, and off-duty police officers converged on the scene, trying to administer first aid.
Paramedics arrived shortly afterwards, but Pawa could not be saved.
Britton said medical examinations revealed one of the stab wounds was 18 centimetres deep.
Defence lawyer Mike Antunovic said Gripp and his cousin had been working at a property in Kāpiti during the day, laying bricks.
They were on their way to play on the poker machines when they stopped to order food and ran into Pawa's group.
"When they parked up on the side of the road intending it to be a very brief stay, they were attacked," Antunovic said.
"This attack was, from the defendant's point of view, sudden, and it was vicious, and it was unrelenting, and it was most certainly unwelcome."
He said all four of the members of the other group were intoxicated and "intent on violence", and that Gripp acted in defence of himself and his cousin.
The trial continues before Justice Robert Dobson and a jury of eight women and four men.
It is set to last two weeks.