Matenga (22) will be making his starting debut at lock for Otago against Canterbury in the Ranfurly Shield challenge.
Matenga was born and bred in Christchurch, and went to Christchurch Boys High School where he played in the First XV.
He played alongside Stephen Brett, Tim Bateman, Nasi Manu, Peter Borlase and James Paterson, all of whom are playing for Canterbury today.
"There is a bit of banter here and there but it will be different on game day. There'll be no friends then," Matenga said.
"It was a real big rugby school and the last year I was there we won the Moascar Cup and got into the top four."
When Matenga was starting out at Christchurch Boys High School, his support peer leader was Adam Thomson, while Daniel Carter was playing in the inside backs for the First XV.
Matenga eventually followed Thomson south, after finishing his schooling, and graduated earlier this year with marketing and tourism degrees from the University of Otago.
With studies now over, he is concentrating on rugby, and nothing comes bigger in the Otago jersey than a Ranfurly Shield challenge.
"It's not often you have a Shield match that is a second chance for the season. We made a few handling errors in that first game and missed a few tackles. If we just delete them, then things will come right.
"The majority of that first game, for the first 60 minutes anyway, we were the dominant team. We need a full 80-minute performance."
Matenga said the whole team was buying into the team pattern, and it was individual errors players needed to cut out for the team to put on a complete performance.
He played most of the club season on the blindside flank for University A but has been placed at lock to replace Tom Donnelly, who is on All Black duty.
Matenga will be asked to mark some tall timber in Sam Whitelock and James Broadhurst but with lifting the way it is, he should be able to handle himself.
"I'd probably prefer to play loose forward but am comfortable playing at lock. I've played quite a few games there. It's more of a tighter role, grafting away, while on the blindside you get to run with the ball a bit more often."
About 130 tickets were sold for an Otago zone at AMI stadium today.
About 11,000 tickets have been sold to the game.
The Bog bar in Christchurch will give all Otago supporters a free drink on presentation of a game ticket after the game.
