The mounting injury toll at the Blues will not help Luatua's task. Flanker Luke Braid's immediate future is uncertain due to his third concussion of the season in the 41-24 victory over the Force, with first-five Dan Bowden also out with a groin strain and fullback Charles Piutau sidelined by a knee injury.
Utility back Matt McGahan, 22, the son of former Kiwis league international Hugh, has joined the team for the rest of the season, with loose forwards Airi Hunt and Jack Ram also in as cover but for a shorter period. Hunt, a 20-year-old from the Waitemata club is a 1.95m and 120kg loose forward who has been in the Blues Development team for the past two years. Ram, 28, plays for Northland and is a former Tonga international.
Luatua was kept on the bench last weekend by rising star Akira Ioane but performed well when replacing Kaino, and Kirwan said the captaincy would help Luatua develop.
"This experience will help Steven grow as a leader and player and it will be a great support for Jerome in the coming years."
Luatua, 24, said the victory over the Force would give the Blues confidence and that every player had to stand up in the wake of the injuries.
Bowden is likely to be replaced by Ihaia West, with Simon Hickey as his back-up.
"The guys who might not have got many minutes, they know this is their time," Luatua said.
Blues' run home
• Friday v Rebels in Melbourne
• Friday, May 15 v Bulls at Eden Park
• Saturday, May 23 v Hurricanes at Eden Park
• Saturday, June 6 v Crusaders at Eden Park
• Friday, June 12 v Highlanders at Eden Park.