Barring a defeat of historically bad proportions to Argentina today, Andy Farrell can chalk 2021 down as a success.

It started in Cardiff with a Six Nations defeat to Wales, a 14-man performance that impressed in spite of the result. The lull that followed against France, Italy and Scotland quickly brought the stock price back down.

The England game was the catalyst, the day that something sparked in Farrell's gameplan. The summer Tests against Japan and the USA were about experimentation, before Ireland pressed into the higher gears this month.

Following last week's win - and attacking intent - against New Zealand, the pressure is off Andy Farrell for the final Test of 2021 against Argentina, although that's not to say the intensity can afford to dip.

Mario Ledesma's side are a perfect match for Ireland this week, and have weapons all around the pitch to test Farrell's new plan.

"That's a lot of continuity there, a lot of firepower," said Farrell this week when asked to assess Los Pumas.

"We know, having watched them against Italy and certainly the game in Paris in a couple of weeks ago, what's coming our way and obviously there's a few lads that haven't played against them before so I'm expecting it will be one hell of a battle.

"They're always going to be dangerous, we know what type of battle it's going to be and we will certainly be prepared for that. But we also know they can be unorthodox in the way that they play if they get go-forward with opportunities to offload the ball.

"We're also aware of the fact that it's not so long ago that they beat the best team in the world."

Argentina's 2021 form may not be pretty; losing six out of six in the Rugby Championship, before a further defeat to France in Paris, finally breaking their duck last week with a 37-16 win against Italy in Treviso.

Hooker Julian Montoya will captain Los Pumas against Ireland

However, all six of their Rugby Championship games were away from home, the first two in South Africa, before the tournament was played to a conclusion in Australia.

In the forwards pack, Andrew Porter is still in the infancy of big-game experience at loosehead, and the more Test minutes he can log in the number one jersey the better.

Covid-19 has effected the Ledesma's side arguably more than any other Tier One rugby nation; they haven't had a home Rugby Championship game since 2019, while their Super Rugby franchise Jaguares have been locked out of the new regional formats, having made huge strides leading up to 2020.

Their 29-20 defeat to France was a true reflection of what they can bring to the party. Forwards like Julian Montoya, Tomas Lavanini, Pablo Matera and Marcos Kremer that just love confrontation and collisions, and backs like Tomas Cubelli and Emiliano Boffelli that thrive off fast, loose ball.

After a settled matchday 23 against Japan and New Zealand, two impressive wins have allowed Farrell the scope to try out his wider squad against the Pumas.

While some fans may have preferred to see more than the four changes in total, there's merit to some continuity.

In the forwards pack, Andrew Porter is still in the infancy of big-game experience at loosehead, and the more Test minutes he can log in the number one jersey the better.

A third successive start for Tadhg Furlong seems unnecessary though. With Porter now on the loosehead side and John Ryan of Munster seemingly out of consideration, Finlay Bealham and Tom O'Toole look to be fighting it out in the short term to be Furlong's back-up.

Bealham is leading that race now, and the high-quality opposition and relatively low pressure environment of this weekend seemed an ideal opportunity to put him in a starting role. Instead, Farrell has opted to give O'Toole (below) some minutes from the bench, resulting in Furlong starting once again.

Having missed out on the games against Japan and the All Blacks due to illness, it's been a frustrating November for Gavin Coombes, who along with Ryan Baird had been a player many hoped would start this Sunday.

Indeed, both Bernard Jackman and Donal Lenihan were unanimous in agreement that the Munster man should start the final Test of the year. November will have been a frustrating month for both players who - barring a late injury - won't have seen any game time.

The lack of changes in the forward pack might be explained by the enforced changes in the backline.

It's unclear how Farrell would have picked his side had Jamison Gibson-Park and Johnny Sexton both been fit this week, but respective thigh and knee injuries have forced him to change his half-backs.

Conor Murray returns to the starting scrum-half jersey, while Joey Carbery replaces Johnny Sexton at number 10.

On paper, it looks like the perfect game for Carbery to step up his progression in.

The 26-year-old carried a lot of pressure into this month following a patchy start to the season in the United Rugby Championship.

His 19 minutes against Japan came with the game fractured and beyond doubt, while his quarter of an hour versus New Zealand was high pressure rugby, where he was more responsible for keeping the ship moving rather than deciding its course.

Ireland were 28-17 winners in the last meeting between the sides in 2018

Having been inconsistent off the tee in the URC, his three successful kicks at goal to push Ireland clear against New Zealand will have been a massive confidence boost to a player still figuring out his groove, in particular the second of those penalties which was right on the limit of his range.

Starting alongside his Munster teammate Murray brings another layer of familiarity that should ease him into Sunday's contest, and a strong performance will allay a lot of the fears about Ireland's succession plan at out-half heading into the Six Nations.

The return to fitness of Robbie Henshaw was always likely to see him get a start, as he joins Gary Ringrose in midfield, while those Irish fans who have been calling for the younger faces will be delighted to see Robert Baloucoune's name on the teamsheet, with the Ulster flier coming in to replace Andrew Conway.

Baloucoune looked electric in his summer debut against the USA, with the stakes and quality of opposition raised once again against Argentina.

While the pressure is off Farrell to an extent following the win against New Zealand, they have set a benchmark for performance over the next two years which the supporters will now expect to be met on a regular basis.

That brings a pressure of its own, as does the individual pressure on the shoulders of Carbery, Baloucoune and Murray; this is their chance to impress.

Even for someone of Henshaw's pedigree, arguably Ireland's best player of the last 18 months and a standout British and Irish Lion Test player, he's watched Ringrose and Aki flourish in his absence this month.

Since Aki made his Ireland debut four years ago, injuries and suspensions have conspired so often to rule out at least one of the trio for seemingly every international window. Looking back across the last four years, it's difficult to establish a consensus first choice centre considering how rarely all three have been available. The lesson to learn is that if you have a clear shot, take it.

If there is a checklist of things for Ireland to do this afternoon, the two main boxes to tick are winning the game, and continuing the ideology of the last two weeks.

The forwards need to offer up the same options around the field, whether they're popping up as carriers, distributors or decoy runners.

The short carries have to pack the same punch as they have for the last two weekends, while the backs need to target the same linespeed in defence and willingness to go wide in attack when the opportunity presents itself.

If they do that, the game is theirs to win.

Verdict: Ireland win

Ireland: Hugo Keenan; Robert Baloucoune, Garry Ringrose, Robbie Henshaw, James Lowe; Joey Carbery, Conor Murray; Andrew Porter, Ronan Kelleher, Tadhg Furlong; Iain Henderson, James Ryan (capt), Caelan Doris, Josh van der Flier, Jack Conan.

Replacements: Dan Sheehan, Cian Healy, Tom O'Toole, Tadhg Beirne, Peter O’Mahony, Craig Casey, Harry Byrne, Keith Earls.

Argentina: Emiliano Boffelli; Mateo Carreras, Matias Moroni, Jeronimo de la Fuente, Lucio Cinti Luna; Santiago Carreras, Tomas Cubelli; Thomas Gallo, Julian Montoya (capt), Francisco Gomez Kodela; Guido Petti, Tomas Lavanini; Santiago Grondona, Marcos Kremer, Pablo Matera.

Replacements: Facundo Bosch, Ignacio Calles, Eduardo Bello, Lucas Paulos, Facundo Isa, Gonzalo Bertranou, Nicolas Sanchez, Facundo Cordero.

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