Porter starts ahead of the injured Tadhg Furlong
The juxtaposition is not great: Warren Gatland cheerfully announces the return to his side of three healed Lions; Joe Schmidt confirms the departure of two wounded ones.
The history of Ireland and Wales in the Six Nations is unusual given the success of each team in the other's back yard. Between 2001 and 2013 Ireland won five of their seven Championship ties in Cardiff. And of Wales's last six visits to Dublin in the Six Nations they have lost just twice. So it's hardly a scary trip for either team. And getting a leg up on the injury front will make this all the more attractive for Gatland.
It would be a surprise if he doesn't look to ramp up the pressure on Andrew Porter, for whom this is massive. And, like his very early introduction against Italy a fortnight ago, unscheduled. That day he was on the field inside five minutes and returned remarkable stats of 13 carries and seven tackles on what was his Six Nations debut. That gave him a better carrying stat, in less than a full match, than 23 other props over the opening two rounds.
It's inconceivable however that Porter will be getting as much go-forward against Wales as he did against Italy. And facing an all Scarlets front row, you'd expect Rob Evans and Ken Owens to attack the Ireland tight head in the hope of getting penalties from referee Glen Jackson.
On the face of it the presence of Porter in the starting pack alongside James Ryan and Dan Leavy puts Ireland on the light side of the experience register, with just 15 caps between them. They are not up against a man-eating unit in red but they are all veterans of the pro game - four of them Lions, like Ireland. That group includes Cory Hill.
It's worth remembering that his elevation to that status was widely scorned last summer, given the manner of Gatland's parachuting in of replacements to protect the Test team. Not too many have questioned his credentials since then. He is a very good rugby player whose form deserves being a part of this pack.
The discipline of the Welsh forwards against England was remarkable in a team stat of just two penalties conceded, the best of any side over the two rounds. They will fancy their chances of getting even more traction against Ireland, especially with Iain Henderson missing.
This will be a brutal affair. Chris Farrell is a good bit more than a bosher but his physical presence in midfield will be a big part of this Ireland performance. With Jared Payne, Garry Ringrose and Robbie Henshaw out of the frame Joe Schmidt didn't have to think too long about a partner for Bundee Aki. Neither will he have been slow to dial up CJ Stander at eight and Fergus McFadden on the bench. The speculation that Keith Earls might move to centre was daft: why would you compromise the form of a wing at the top of his game to pitch him into a slaughter house battle in midfield?
Any more casualties in that area on Saturday and Schmidt will be sweating. Indeed his temperature is probably rising already.