Pomana then kicked Haynes twice to the head "with great force", swinging his leg "like soccer kicks".
The judge says the victim had been attacked in a "cowardly and brutal manner when he was down and defenceless".
Kala and Pomana were found guilty of manslaughter earlier this year and have today been sentenced, with Pomana receiving nine years in prison and Kala seven years.
"Both of you unlawfully Killed Mr Haynes. You cut short the life of a good man," Justice Bruno Fiannaca told the two guilty men in court.
Kala, who was born in New Zealand, had worked for the Ashburton Aboriginal Corporation and had a young son.
Pomana will likely be deported following his release.
Both men will be eligible for parole.