"I was getting into parties and drugs, boozing and marijuana, with my mates, fighting and stuff.
"I didn't commit any crimes, but was just up to no good. I was just getting up to mischief but that's all in the past now.
"They set me straight and I started setting goals. They changed my life really."
Christchurch-born and raised in Palmerston North before moving to Auckland, Tevaga is quick to list his father as "a huge role model", but his dad's army career meant Tevaga often missed a male presence around the home.
The Taplins are renowned for their work as rugby league caregivers and are now employed by the Warriors to look after five rising young players in the club's Howick share house. The duo previously worked in the same capacity for the Sydney Roosters and share a gift and passion for helping develop young players on and off the field.
Tevaga explains the pair made him feel at ease and enabled him to be honest in revealing the bad behaviour and negative influences that were having a detrimental effect on his life.
"He asked what I was up to outside of footy and I just told him the truth and opened up to him," he said. "They asked me what I wanted to do in life and he made me realise I wasn't going to get there doing the stuff I was doing.
"To really give it a crack I had to give up that stuff, so I did."
Spencer downplays his role and influence over the promising back-rower turned hooker, but says it was clear in 2012 that a 17-year-old Tevaga was in need of some direction.
"That's all he was looking for really, some guidance and boundaries," he said. "That's just like any young man, without them they're a bit wayward about where they want to head in life.
"Some of those kids, especially Jazz, would cling to you, and once I knew his story I understood why.
"We had our differences as coach and player but behind all of that gradually he understood I was trying to help him.
"It took him a bit to realise I was trying to teach him about footy but at the same time some off-field life skills."
Having turned the corner in his own life and career, Tevaga hopes his story can help others. He now gets his kicks not from booze or illicit substances but playing the game he loves on the big stage.
"Playing league, that's where I get my high now and I just love it."