A 13-year-old boy told the police he had previously kept quiet about his rugby coach's sexual abuse because he didn't trust anyone.
The 13 year-old's DVD police interview has been played to a closed court room at the High Court in Auckland.
His former coach, Alosio Taimo, is on trial and has denied 83 charges of sexual offending against 18 boys over nearly 30 years.
Mr Taimo also worked as a teacher's aide. The boy said the the 55-year-old had won over the trust of his parents and the parents of his friends but the grown-ups didn't know what was going on.
The teenager told police the abuse started happening when he was just 10 or 11-years-old.
He said he and other boys called Mr Taimo "Mister".
They would go to his South Auckland home where he would let them play video games and watch movies on his laptop.
The boy said "Mister" would also call the boys into his bedroom.
He recalled the first time it happened and looking back at his friends as he walked towards Mr Taimo's bedroom. He said his friends looked "shocked".
Once in the bedroom, Mr Taimo handed him oil that he kept in his toiletry bag and asked him to massage his shoulder.
The touching soon became sexual.
He said on one occasion Mr Taimo showed him pornography on his laptop. On another occasion he said Mr Taimo touched him in front of another boy.
He said the abuse happened "heaps" and up to 30 times.
"He only picked people he trusts. He picked his victims," he said.
On one occasion he woke up to find Mr Taimo touching him and told him to "get lost".
"That's when he started crying... He was crying and bragging about what he does for us."
He said at one point Mr Taimo said: "I do everything for you and this is how you pay me back."
The teenager described the sex abuse also happening in Mr Taimo's car and in the school sports shed.
"He wanted things his way - if he didn't get what he wanted, he'd be grumpy."
He said he also found naked pictures of boys on Mr Taimo's phone. He deleted them and went back to playing a game on the device.
The abuse was exposed when one day the boy was talking to his cousins. He had asked if they had been touched by "Mister" and when they said no, he told them of his experiences.
His auntie was doing the laundry at the time but walked into the room and heard part of the conversation.
The boy said his auntie asked what had happened.
"I said: 'Mister has been touching me'. I told her ... She believed me."
He said his auntie looked angry and told the other children to go to their room.
"When I finished telling her, she was crying."
The teenager said his aunt's son - his cousin - had also spent time in Mr Taimo's care. His aunt phoned her son and he also confirmed he had been sexually abused.
"She said: 'I can't hide it, I can't hide it. Something has to happen'.
"She said she was proud of me ... That I was brave ... That I'm a champion."
The teenager said his aunt gave him a hug and convinced him to tell his mother.
The police were called in to investigate shortly afterwards.
The trial, before Justice Moore and a jury, has been set down for 10 weeks.