The 28-year-old Newport Gwent Dragons forward is among six Test rookies in Wales' Six Nations squad, being joined by Olly Kohn, Eli Walker, James King, Josh Navidi and Andries Pretorius.
But it is understood that former computer software salesman Coombs, who only made his Dragons debut less than three years ago, might have done enough to be fast-tracked straight into the Six Nations arena.
Wales' interim head coach Rob Howley has seen the second-row department ravaged by injuries, with Alun-Wyn Jones, Luke Charteris and Bradley Davies all currently unavailable, while Ian Evans has not played since the autumn Tests because of knee trouble.
Howley has an option of moving versatile former Wales captain Ryan Jones - provided he has recovered from a dislocated thumb - into the second-row or there are other possibilities like Kohn, King or Lou Reed. But with Evans likely to start, it would appear that Coombs has emerged as front-runner to be his second-row partner.
Howley is due to unveil the starting XV on Thursday, with one enforced switch in a tried and tested back division set to see Ospreys fly-half Dan Biggar replace long-term injury victim Rhys Priestland.
Second-row apart, most attention will focus on the back-row, where it has not been dismissed at any juncture that Wales could hand skipper Sam Warburton the number six shirt and field in-form Ospreys openside Justin Tipuric alongside him.
Whatever happens in selection, though, Wales know the importance of making a winning start, both with regard to establishing Six Nations momentum and ending a seven-game losing run.
They have beaten Ireland three times in succession - including a 2011 World Cup quarter-final victory - although Wales last toppled another Test-playing country more than 10 months ago.
"Yes, there are some established players who are unavailable due to injury, but I think we've got a great mix of players," Wales attack coach Mark Jones said. "We are confident we can go out and put on a good display. I think if we can do that then we will have every chance of getting a positive result."