Chris Farrell and Bundee Aki will both earn their second caps against Argentina as Robbie Henshaw's hamstring injury has forced Joe Schmidt into selecting a new midfield pairing.
There are three changes to the starting XV that recorded a record victory over South Africa two weeks ago.
The Ireland head coach this afternoon named his matchday squad to face the Pumas in the third and final Test of the Guinness Series at the Aviva Stadium on Saturday and it will be a red letter day for two young Leinster players.
In-form wing Adam Byrne will make his debut on the right wing in place of Andrew Conway, while second-row James Ryan will make his first Test start, in place of Devin Toner.
Toner and Conway were the only players to start against South Africa and last week's narrow victory over Fiji.
Rory Best will captain the side from hooker, with the Leinster pairing of Cian Healy and Tadhg Furlong on either side of the Ulster man.
"No point looking two years back - you must look forward" Joe Schmidt on why facing Argentina now is not a grudge match pic.twitter.com/BI7aJ9FTSz— RTÉ Rugby (@RTErugby) November 23, 2017
Iain Henderson will partner Ryan in a new-look, physically imposing second-row, whiel Schmidt understandably sticks with his Lions back-row of Peter O'Mahony, Sean O'Brien and CJ Stander.
Jonathan Sexton and Conor Murray are the half-back pairing that pick themselves, while Ulster's exciting Jacob Stockdale will join Rob Kearney and Byrne in the back three.
There is a 50/50 split on the bench, with four Leinster and four Munster men among the eight replacements. Ian Keatley will back-up Sexton in the enforced absence of Joey Carbery.
Commenting om Adam Byrne's inclusion, coach Schmidt said: "With all the wingers that we brought in we wanted to have a look at how they trained and how they fitted in. He has given us the confidence to include him because he has worked really hard and is picking things up all the time.
"With a bit of experience in the backline around him. I'm really hopeful he gets a good first outing in an Irish jersey."
Absent from the starting XV Robbie Henshaw. The player missed training today, leaving him unable to contest selection to face the Pumas.
Schmidt admitted Henshaw has picked up a hamstring issue and insisted Ireland were not ready to risk one of their top assets.
He's got a slight hamstring strain," said the coach.
"I think at a push he could potentially have been involved.
"But it should see him fine for what's coming up (with Leinster), he's got a busy period coming up.
"This window was a chance to see how guys do in pressure situations.
"Chris (Farrell) acquitted himself pretty well last week, got better as the game went on, and it's another opportunity for him."
Ireland (v Argentina): Rob Kearney; Adam Byrne, Chris Farrell, Bundee Aki, Jacob Stockdale; Johnny Sexton, Conor Murray; Cian Healy, Rory Best, Tadhg Furlong; James Ryan, Iain Henderson; Peter O’Mahony, Sean O’Brien, CJ Stander.
Reps: James Tracy, Dave Kilcoyne, John Ryan, Devin Toner, Rhys Ruddock, Luke McGrath, Ian Keatley, Andrew Conway.
Live coverage of Ireland v Argentina begins on Saturday on RTÉ 2 television and RTÉ Player at 4.30. Live commentary is on RTÉ Radio 1’s Saturday Sport, which starts at 2.45, and you can follow all of the build-up and action on our live blog online at rte.ie/sport and on the News Now app.