The hooker has become almost the forgotten man for Otago and All Black rugby, but it is hardly his fault. He has become an almost professional trainer as he sits between the cracks for the All Blacks and Otago.
The 28-year-old has been training with the All Blacks for the Rugby Championship these past few weeks, and when he will actually join up with Otago is up in the air.
Coltman was not named in the Rugby Championship squad, but is training with the national squad.
He is filling the shoes of Dane Coles, who has been named in the Rugby Championship squad but is not yet fit enough to train with the team.
So Coltman is doing his bit and presumably would be called into the match-day squad if either Nathan Harris or Codie Taylor was injured.
Coltman last started for Otago in early September, 2016, when Otago beat Bay of Plenty in Tauranga.
He was called into the All Blacks that season as cover and stayed with them for most of the season, although he came back to play one further game off the bench for Otago in its run to the championship final.
He wanted to play in the championship final on October 2, 2016, but was ruled not available by the national selectors as he was heading away on an end-of-year All Black tour.
He ended up making his All Black debut on November 12 against Italy.
Coltman did not play at all for Otago last year because of a nasty ankle injury picked up playing for the Highlanders in July.
He was part of the All Black squad this year and ended up coming off the bench in the third test against France near the end of the game.
It must be somewhat frustrating for Coltman to just train all week and not get a game, but the national selectors need cover at hooker, and that is where Coltman sits.
Otago coach Ben Herring was comfortable with the situation of Coltman training with the All Blacks.
Coltman has played 64 games for Otago, the most of any player in the Otago squad.
Otago is blessed with some good hookers in its side. Skipper Sam Anderson-Heather, Sekonaia Pole and Ricky Jackson are all quality rakes.