Tries: Tomas Leonardi, Juan Martin Fernandez Lobbe
Pens: Sanchez 4
Ireland produced a brilliant seven-try display to hammer Argentina and guarantee a crucial top-eight ranking ahead of the 2015 World Cup draw.
The superb Craig Gilroy, Jonathan Sexton, Richardt Strauss and Simon Zebo notched first-half tries for the Irish as they led 24-9 at the interval.
Sexton's second try was followed by two more Tommy Bowe touchdowns in the second half by the dominant Irish.
Tomas Leonardi and Juan Martin Fernandez Lobbe managed late replies.
However, the two Pumas tries in the closing five minutes took little gloss off a hugely impressive Irish display.
Ireland started the match with the danger of dropping into the third tier of seeds for the next World Cup hanging over them and with some pundits even suggesting that defeat could put Declan Kidney's future in doubt.
Early Irish nerves were exhibited by Sexton's kick-off going straight into touch and Argentina fly-half Sanchez then hit the woodwork with a penalty chance from 40 metres.
However, Sexton gave a hint to the home side's attacking intentions as he opted to kick for the corner when presented with a chance for points from distance.
The home team's desire to run the ball, off the platform of a dominant set-piece, seemed to be taking the Pumas by surprise.
Slack Argentine defending gifted the Irish their first try in the 10th minute as Test debutant Gilroy danced past three weak tackles to score after Murray's quick dart into the 22 after a line out.
Irish concentration wavered at the restart as they were caught offside which allowed Sanchez to reply from 30 metres.
But it was a brief respite for the Pumas as Gilroy's dancing feet again saw the Irish breach the gain-line two minutes later with the second try coming after Sexton evaded some more dreadful tackling to score after Gordon D'Arcy's pop-pass.
Once again, the Pumas replied straight from the restart with Sanchez punishing a Keith Earls offence at the breakdown, but in truth the visitors were living off scraps.
Argentina were beginning to look shell-shocked in the 21st minute as another virtually uncontested line-out in the Pumas 22 saw hooker Strauss peel off the back of the maul to score at the corner flag.
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The visitors should have notched a try of their own in the 29th minute as the predatory Juan Jose Imhoff looked set to score under the posts only to be denied three yards short of the line by the impressive Donnacha Ryan and Zebo.
The Pumas' chance did yield a third penalty for Sanchez but the poor return from Argentina's brief flurry was emphasised as Ireland poached their fourth try within two minutes after Bowe's high fetch in midfield.
With confidence oozing in the Irish backs, Sexton's flat pass took two defenders out and enabled Zebo to score his first Ireland try as the home side led 24-9 at the break.
Argentina needed a fast start to the third quarter but while Sanchez did notch his fourth penalty after the restart, Ireland were soon back in total control another Sexton penalty was followed by Bowe's 47th-minute try.
Sexton was the architect of the try as Bowe won the race to gather the fly-half's clever chip behind the hapless Argentina defence.
Provider Sexton then turned scorer as he was on Keith Earls' shoulder to take a pass before side-stepping scrum-half Martin Landajo's attempted tackle to cross over in the corner.
The game was turning into the kind of rout that no-one had seen coming.
Not surprisingly, the pace then dropped with the outcome long having been decided before Bowe notched his 26th international try seven minutes from time after more awful defending by the visitors.
Leonardi and captain Fernandez Lobbe barged over for late tries but the scores were little consolation for the well-beaten visitors.
McFadden for Bowe (74), O'Gara for Sexton (72), Reddan for Murray (72), Kilcoyne for Healy (74), Cronin for Strauss (74), Bent for Ross (68), O'Callaghan for McCarthy (63), Henderson for O'Mahony (72).
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