Both players are vying for the third hooking berth in the All Blacks squad for the team's four-test European tour, while the New Zealand Maori side also have a trip to England in November and both rakes have previously turned out for the Jamie Joseph-coached Maori team.
Whether incumbent All Blacks Keven Mealamu, 33, and Andrew Hore, 34, can both play on until the next World Cup remains to be seen but the reality is that Steve Hansen and Co need to find a successor or two.
Wellington's Coles and Hawkes Bay's Elliot are the best placed to succeed Mealamu and Hore but there is daylight between the two pairs and a further distance back to the peloton behind Coles and Elliot.
Elliot has played three tests since his debut in 2010 and got on the paddock once against Ireland in June, while Coles was called in to a training camp with the All Blacks in early August.
Both have shown impressive flashes during this year's ITM Cup campaign and Elliot said he had focused on one thing for the Magpies.
"Just consistency," the 26-year-old said. "I was fortunate enough to be picked in that June test series. So if I can just concentrate on my game for Hawkes Bay and really push my case, hopefully I get to go on that end of year tour.
"I feel that I've been knocking on the door since 2008 when I was first selected in the All Blacks squad. But the likes of Keven and Andrew Hore, who have been around for a decade now, it's always going to be hard to push them off their perch. But I feel like I've come of age in the last couple of years so let's hope that I can further my career with the All Blacks."
Coles, 25, is a tough player to miss with ball in hand. Earlier in his career there were suggestions he was too loose, but he has developed during the past 12 months, which included starting all 16 of the Hurricanes' games this year.
His lineout throwing was an issue during the Super Rugby competition, including one forgettable outing where he produced three "not-straights" against the Crusaders.
It is something he acknowledged he was trying to remedy and pointed out that Wellington's lineout during the ITM Cup had been one of the most accurate in the competition.
"I think it's going OK but nothing's ever perfect so I've still got to keep working hard in the week because if you stop doing it it's going to affect you in the game," Coles said.
Both players will have at least one more chance to show their wares to Hansen in the final round of the ITM Cup's regular season.
Former All Blacks hooker Derren Witcombe, who played five tests in 2005, and is now part of the coaching set-up for Northland, said making the step up from provincial and Super Rugby was down to execution.
"I think really just do the basics well and to a high level," he said.
"The team can't play if you can't throw the ball, the team can't play if you don't win your own scrums so as far as looking to forwards, you've got to do your core roles to the highest level and I guess it just depends on who's doing that really to the highest level in the ITM Cup.
"I think there's still a pathway to the All Blacks - you just have to raise the bar personally against your opposition and be a bit more clinical."
