There were some interesting selections - some enforced - for the one-off Test that serves as a sounding board for Farrell as he prepares his troops to take on the Wallabies in Australia.
Here Flashscore looks at three things he will hope to take away from Friday’s Test against the Pumas…
Marcus and Fin Smith the playmaking duo once more
We heard about it all through the Six Nations, and now we get to hear about it in a different jersey. Steve Borthwick’s Championship selection headache revolved around the two playmaking Smiths who were both capable of leading proceedings in the number 10 jersey. Marcus Smith started the first game of the Six Nations - a loss to Ireland - while Fin Smith sat on the bench.
Thereafter Fin Smith was given fly-half duties, with Marcus Smith starting at full-back for three of the four remaining games - all of which England won.
Debate around the pair roared through England’s campaign, with some saying Marcus Smith lacked the defensive pedigree to form the last line, while others argued that what he brought in attack made up for any potential defensive frailties.
Farrell is not short of full-back options. Blair Kinghorn, seen by many as the likely candidate to wear the 15 jersey in the Tests, is still on duty with Toulouse so could not be picked for this game, while Hugo Keenan missed Leinster’s URC title-winning victory over the Bulls on Saturday due a calf complaint so is not fully fit.
Perhaps Farrell is making do with what he has at his disposal, or maybe he’s looking at what Marcus Smith can do from the back in a big game against better opposition than some of the midweek games will offer. Time will tell, but the familiarity of serving in that role through February and March will no doubt stand Marcus Smith in good stead this weekend as he stakes his claim to a Test place.
All eyes on Furlong and Bealham
Keenan is not the only Leinster player with a calf niggle. Tighthead prop Furlong, a third-time tourist, is likely to be an important figure on the tour of Australia but is struggling to shake off an injury complaint of his own.
He was the anchor of the Lions scrum in South Africa, holding his own against the scrummaging power of the Springboks and making sure his team had a good platform to work from in 2021.
The Wallabies pose a far lesser threat at scrum time, but the Lions themselves are not quite as rich in tighthead options this time around; Scotland's Zander Fagerson was ruled out of the tour through injury, prompting a late call-up for Ireland's Finlay Bealham.
Bealham has been handed the starting jersey this weekend in what will be a very proud moment for the young prop. A lot of eyes will be on him as he locks horns with Argentine loosehead Mayco Vivas, but there will arguably be even more eyes on Furlong when he takes the field to replace Bealham.
His injury woes have meant he has not played in a game of rugby since Leinster's Champions Cup semi-final defeat by Northampton at the beginning of May, and has only featured nine times in total over the course of the season due to a litany of injury struggles.
With Fagerson gone, a lot of pressure will fall on Furlong to once again anchor things in Australia this summer. Fortunately for Lions fans, Farrell is convinced the Irish tighthead is ready to do just that.
"He's fit and ready to go," Farrell said of Furlong. "He's trained well and as keen as everyone else to get the show on the road."
Tuipulotu and Aki pair up - is a certain Wallaby in mind?
All wisdom pointed to Sione Tuipulotu and Bundee Aki fighting over the inside centre position for the three Tests, but Farrell has flipped the script and put the two together in midfield this weekend.
Their playing styles are remarkably similar, using raw power and pace to punch holes through defences. Both can handle well and pose a threat out wide, but it is in their directness where they have both made their name.
It means we will see a lot of barnstorming running at Argentina this weekend, but is Farrell testing out this combination with other opponents in mind?
Australia's star player - or at least the player with the biggest x factor - by some distance is Joseph-Aukuso Suaalii.
The 21-year-old former rugby league star has already made waves in rugby union, making his Australia debut against England at Twickenham in November - spearheading an unlikely win for the visitors with a stand-out performance.
Farrell will be well aware of the threat posed by Suaalii, and whether it be he's thinking about putting the centre under early pressure with plenty of defensive duties, or that he will just have two big-tackling opponents in front of him at all times, it's hard not to think this move is with the rising star in mind.
Australia have a lot of other firepower, and the Lions have plenty of midfield options at their disposal, but a showdown between a Tuipulotu and Aki pairing and Suaalii would be worth the ticket price alone.
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