Coombs was named in the starting XV announced by interim head coach Rob Howley on Thursday, after a second row injury crisis left Wales without several experienced locks, and he will pack down alongside Ian Evans, who has himself been struggling with knee trouble.
But there was no place for the side for in-form openside Justin Tipuric.
Wales captain Sam Warburton retained the No 7 shirt with Aaron Shingler at blindside flanker and Tipuric on the bench for this Millennium Stadium match.
In the backs, Ospreys playmaker Dan Biggar filled the key role of flyhalf vacated by the injured Rhys Priestland, with Wales looking to end a run of seven successive Test defeats this weekend.
Teams:
Wales:
15-Leigh Halfpenny, 14-Alex Cuthbert, 13-Jonathan Davies, 12-Jamie Roberts, 11-George North, 10-Dan Biggar, 9-Mike Phillips; 1-Gethin Jenkins, 2-Matthew Rees, 3-Adam Jones, 4-Andrew Coombs, 5-Ian Evans, 6-Aaron Shingler, 7-Sam Warburton (captain), 8-Toby Faletau.
Substitutes: 16-Ken Owens, 17-Paul James, 18-Craig Mitchell, 19-Olly Kohn, 20-Justin Tipuric, 21-Lloyd Williams, 22-James Hook, 23-Scott Williams
Ireland:
15 Rob Kearney; 14 Craig Gilroy, 13 Brian O'Driscoll, 12 Gordon D'Arcy, 11 Simon Zebo; 10 Jonathan Sexton, 9 Conor Murray; 8 Jamie Heaslip (captain), 7 Sean O'Brien, 6 Peter O'Mahony; 5 Donnacha Ryan, 4 Mike McCarthy; 3 Mike Ross, 2 Rory Best, 1 Cian Healy
Substitutes: 16 Sean Cronin, 17 David Kilcoyne, 18 Declan Fitzpatrick, 19 Donncha O'Callaghan, 20 Chris Henry, 21 Eoin Reddan, 22 Ronan O'Gara, 23 Keith Earls