The 24-year-old Retallick's partnership with Sam Whitelock, with Luke Romano in reserve, is such that Steve Hansen and his coaches have opted to take only three locks to the tournament. Jerome Kaino and Victor Vito will be used as possible lock cover, their versatility allowing the All Blacks to take an extra loose forward - a traditionally injury-prone position - while allowing for extra speed on the bench as they attempt to play the game at pace.
Retallick insisted he was happy with the potential extra workload and his ability to play through pain was probably one of the reasons Hansen decided to take only three specialist second-rowers.
Retallick injured an ankle before the All Blacks played the Springboks in a Rugby Championship test in Johannesburg this year but pushed through the pain barrier to help deliver his team to an impressive come-from-behind 27-20 victory.
"He assured us he was okay but I think it's a testament to his courage and his mental fortitude and toughness that he actually got through the game," Hansen said at the time.
"He got another belt on it in the far corner and re-taped it, so he should be pretty proud of himself and we're very proud of him."
Vintage World Cup
All Black World Cup veterans
Tony Woodcock, Ben Franks, Owen Franks, Keven Mealamu, Richie McCaw, Kieran Read, Jerome Kaino, Victor Vito, Sam Whitelock, Dan Carter, Colin Slade, Ma'a Nonu, Conrad Smith, Sonny Bill Williams.
Most experienced RWC squads
1. New Zealand 1484 caps
2. South Africa 1297
3. Georgia 1253
Players with 50 caps or more
1. Australia 13
2. South Africa 11
3. Romania 11
4. New Zealand 10