The former rugby league star and his squad will brood on the defeat during the long flight to Perth, and will arrive desperate to consign the display to history and take out their frustrations on the Force next weekend.
Top of the props
The Lions were missing the majority of their Leinster contingent against Argentina, including loosehead prop Andrew Porter, who in the stand in the Aviva Stadium basking in rare Dublin sunshine.
Ellis Genge was strong in Dublin.Credit: Getty Images
In his place, Englandโs Ellis Genge made life brutally difficult for Pumaโs tighthead Joel Sclavi, winning two clear scrum penalties against the La Rochelle prop in the first half.
Genge also won another set-piece penalty against his replacement, Briveโs Francisco Coria. What is concerning for the Wallabies is that Porter is even stronger in the scrum than his English teammate. Wallabies scrum coach Mike Cron would have taken pages of notes over his morning coffee.
Porter starting and Genge coming off the bench is a monstrous prospect. It is vital that Brumbies skipper Allan Alaalatoa can at least gain parity and then Taniela Tupou hold the Wallabies scrum in the final quarter against a fully firing Genge.
Dealing with pressure
After Santiago Corderoโs spectacular try in the 58th minute, Argentina had to absorb 24 minutes of relentless Lions attacks to hold on to their four-point lead.
One of Farrellโs favourite players, Canberra-raised winger Mack Hansen, looked dangerous every time he touched the ball and it appeared there were more gears for the Lions to move through in attack.
With three minutes left, the Lions were inches away from victory before stand-in captain Tadhg Beirne was penalised for an illegal neck-roll at the breakdown.
Lions series are often won by the smallest of margins and this was a rare moment of indiscipline from a player known for his calmness under pressure. The Wallabies will look to sow doubt in the minds of their opponents at every opportunity.
The battle at the breakdown
The Wallabies squad is thin in parts, particularly the centres and props. But as ever, Australian rugby has an abundance of back-row talent.
The Lions were missing one of the best breakaways in the world in Irelandโs Josh van der Flier, but the combination of Walesโ Jac Morgan and Englandโs Ben Earl and Tom Curry was still a strong unit.
It was notable that winger Rodrigo Isgro earned three turnovers at the breakdown, including one that ultimately won the game for his side.
Tom Curry of British & Irish Lions is tackled Credit: Getty Images
English prodigy Henry Pollock came on for 33 minutes, providing a mixed bag which included a crucial missed tackle on the outstanding Pumas playmaker Tomas Albornoz that led to Corderoโs match-winning try and an abrasive performance in the loose.
Wallabies breakaways Fraser McReight and Carlo Tizzano both have the potential to cause havoc to the Lionsโ ball at the breakdown.
Familiarity will breed comfort for Lions
It was not the Lionsโ strongest side in Dublin, with the likes of Scotlandโs Blair Kinghorn still playing for Toulouse. However, there were plenty of players who will be pushing for selection against the Wallabies.
The Argentine defence was excellent when it came to scrambling against the Lionsโ attack and making crucial reads, knowing exactly when to shoot up and put pressure on the ball-carrier.
In each tour game leading up to the Tests, Farrell will shuffle his deck before deciding whether to stick or twist with his combinations.
One of the ultimate challenges for any Lions player is to unlearn years of programming with their club and country and quickly embrace new attacking patterns.
Farrell has picked a large contingent of tried and tested Leinster players, for the very reason that they are so familiar with one another. Conversely, rested Scottish playmaker Finn Russell delights in unstructured, off-the-cuff play.
This defeat Lions put the Lions under pressure before their plane had even left the tarmac, but they still have time to become a formidable side before the first Test in Brisbane in just under a month.
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