Coltman (26) has been included in the All Black squad for this Saturday's Bledisloe Cup test against Australia in Wellington.
Coltman joined the squad yesterday and is one of five new faces who will provide injury cover for various team members.
Coltman is joined by Blues and North Harbour hooker James Parsons, Chiefs utility backs Damian McKenzie and Seta Temanivalu and young Blues outside back Rieko Ioane.
Hookers Nathan Harris (knee) and Codie Taylor (concussion) were injured last week.
Harris is gone for the season while Taylor will undergo testing this week.
First-choice hooker Dane Coles is carrying a rib injury but still managed to play more than 75 minutes of the test, although he had taken pain medication before the game.
Coltman has featured for the Highlanders and Otago in the past few seasons although his Super rugby season this year was hampered by a nasty toe injury. He has the rugged abrasive game which will suit the All Blacks style.
Coltman, who is rooming with Coles, joined the All Blacks for a week in 2013 as part of an apprenticeship scheme but has never been named as part of a squad. He wins the spot ahead of the likes of Ash Dixon and Hika Elliot.
There had been concerns over Coltman's throwing-in early in his career but it has improved over the past couple of seasons, and he had few missed throws this year.
Coltman's promotion is great for him but will cause Otago coach Cory Brown some headaches as he will have to replace his starting hooker and his captain.
Sekonaia Pole may look to start the Mitre 10 Cup game against Wellington on Thursday night. The captaincy may be handed to No8 Paul Grant or midfield back Tei Walden.
Parsons made an appearance for the All Blacks during the end-of-year tour in 2014 when players went down with injury.
Backs George Moala (knee), Ryan Crotty (head knock) and Waisake Naholo (hamstring) are all unlikely to front up for the All Blacks on Saturday.
Ioane is only 19 but has been viewed by All Black coach Steve Hansen as a player of the future and has some speed and skill in his game.
The Wallabies also have injury concerns after inside centre Matt Giteau suffered two fractures in his left leg in Sydney, while Rob Horne is likely to need a shoulder reconstruction.
Matt Toomua, who had replaced Giteau, also suffered a head knock in Sydney and was then replaced by Horne before he left the field. All three injuries occurred in the first half.
Australia's replacement halfback, Nick Phipps, ended up on the wing and scored a consolation try after the All Blacks had put the game beyond doubt by halftime with a 32-3 lead.
The All Blacks can retain the Bledisloe Cup, the symbol of transtasman supremacy, with a draw on Saturday. They have held the trophy since 2003.
- Additional reporting Reuters