Beirne's brilliance in Chicago wasn't enough to see him retain his place in the second row, or secure a berth on the bench, with Schmidt opting for what appears to be his first-choice pairing of James Ryan and Iain Henderson.
Replacements: 16-Sean Cronin, 17-Jack McGrath, 18-Andrew Porter, 19-Devin Toner, 20-Dan Leavy, 21-Luke McGrath, 22-Joey Carbery, 23-Andrew Conway.
Centre Garry Ringrose is out with injury as Robbie Henshaw comes back in.
"There's got to be a degree of consideration for getting the best players on the pitch, and maybe that's what Mario's looking for, with Guido Petti in the back-row, with Alemanno and Lavanini at lock this weekend", said Ireland boss Schmidt.
"It's probably not a change-up that we foresaw, but at the same time I'm sure there will be some sense to it". I just want them to run harder so they can keep their distance.
"But we know that drives that group forward, and that's exactly what we want from them".
Ireland are hoping his return will help their push towards success at next year's World Cup in Japan where they have legitimate ambitions of success, but O'Brien is only setting himself small targets as he works his way back.
Only five of those have been starts but Marmion is a tried and trusted Schmidt player having been a virtual ever-present around Carton House since his debut back in 2014, and the head coach pointed to his performance against England two years ago as a sign of the 26-year-old's ability to deputise in the nine jersey.
Argentina coach Mario Ledesma has named a XV made up entirely of home-based players.
Argentina should provide a testing examination provided they are not too exhausted having come out of the Rugby Championship with two victories under new head coach Mario Ledesma, including their first in Australia since 1983.
"He was already coaching, he was already contributing", said Schmidt.
"They have very good players, all of them".
"Obviously going through what I've done in the previous year, I've assessed where I am and where I want to be".
"So he's already done an incredible job in broadening his own experiences". So I think he's already compiled some good success which will give him confidence, which will give him confidence, and certainly I know he's got the confidence of the players.