|Ireland (10) 20|
|Tries: Fitzgerald, Murphy Cons: Madigan 2 Pens: Madigan 2|
|Argentina (20) 43|
|Tries: Moroni, Imhoff 2, Tuculet Cons: Sanchez 4 Pens: Sanchez 5|
Argentina's early scoring blitz helped them dash Ireland's hopes of earning a first World Cup semi-final spot.
Brilliant tries from Matias Moroni and Juan Imhoff saw the Pumas take a 17-0 lead over the under-strength Irish by the 13th minute.
Luke Fitzgerald's terrific score helped cut the margin to 20-10 by the break.
A Jordi Murphy touchdown reduced the gap to three points but late tries from Joaquin Tuculet and Imhoff sealed a deserved Argentina win.
The victory sets up a semi-final for the Pumas against Australia at Twickenham next Sunday, with all the remaining teams in the competition from the southern hemisphere.
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Devastating start leaves Ireland stunned
Argentina might be traditionally known as a powerful side that puts their emphasis on their forward play, but they stunned Ireland by playing with pace and width from the first whistle.
None exemplified this more than the lively Moroni, who skated around Dave Kearney to score Argentina's opener after three minutes.
A bad start for Ireland turned into a disastrous one as wing Imhoff ran on to a perfectly judged crossfield kick from Santiago Cordero to touch down again on 10 minutes.
After Imhoff's score, the impeccable Nicolas Sanchez struck his third successful kick to increase Argentina's advantage to 17-0 with less than 15 minutes played.
Match too far for injury-ravaged Irish
Ireland went into Sunday's match without influential performers Paul O'Connell, Johnny Sexton, Peter O'Mahony, Sean O'Brien and Jared Payne - but despite so many key absences they showed huge character to battle their way back into the contest.
Nothing seemed to be going right for the Irish and Tommy Bowe went off with an apparent knee injury.
However, his replacement Fitzgerald gave the Six Nations champions hope as he produced a superb reply on 26 minutes, punishing a loose Cordero kick as he burst past Tuculet following good work by Conor Murray and Robbie Henshaw.
Argentina led by 10 points at the break - but another Fitzgerald break set up flanker Murphy's score after half-time as Ireland cut the margin to 23-20.
Ireland comeback runs out of steam
With Rory Best becoming increasingly influential in the breakdown exchanges, Ireland at one point looked to have enough momentum - as well as vociferous support from the Irish fans inside the stadium - to go all the way into the last four.
However, the Irish could not capitalise on two good chances in the third quarter - the first as intense pressure after 48 minutes failed to yield any points before Ian Madigan missed a long-range penalty chance which would have levelled the contest on 60 minutes.
The effort expended in attempting to recover from their awful start took its toll on the Irish in the closing stages as Tuculet's 68th-minute score ended the game as a contest before Imhoff's second touchdown.
As the devastated Irish left the field at the final whistle, there were huge and emotional celebrations from Pumas, who can look forward to their second World Cup semi-final after reaching the same stage in 2007.
Man of the match - Nicolas Sanchez
Two-try hero Imhoff, Cordero, old stager Juan Martin Fernandez Lobbe and, in fairness, several other Pumas could have been contenders for the man of the match award, but Sanchez kicked 23 of Argentina's points and got the best out of his fellow backs.
'Just the start for Argentina'
BBC pundit and 2003 World Cup winner Matt Dawson: "The consistency of performance is always key to success, and I also believe Argentina have some real game-breakers - players such as Tuculet, Imhoff, Cordero.
"They have probably learned from playing in Europe and playing in the Rugby Championship. They've got a Super 15 franchise too, so this is just the beginning for Argentina."
|7 (1)||Scrums won (lost)||5 (0)|
|10 (0)||Line-outs won (lost)||7 (1)|
|93 (4)||Rucks won (lost)||89 (6)|
|28||Kicks from hand||20|
|125 (27)||Tackles made (missed)||106 (20)|
|Provided by Opta|
- Argentina have now beaten Ireland in three of the four World Cup meetings between the sides
- The 43 points scored by Argentina was the joint most Ireland have conceded in a Rugby World Cup game (v New Zealand, 1995 & v France, 2003)
- Nicolas Sanchez scored 23 points to become the top point scorer in the tournament so far (74); only once has Sanchez scored more in a single Test for the Pumas (25 v Tonga)
- Juan Imhoff scored two tries to become the first Argentina player to score five tries in a single Rugby World Cup tournament
Ireland: Rob Kearney; Tommy Bowe, Keith Earls, Robbie Henshaw, Dave Kearney; Ian Madigan, Conor Murray; Cian Healy, Rory Best, Mike Ross; Devin Toner, Iain Henderson; Jordi Murphy, Chris Henry, Jamie Heaslip.
Replacements: Richardt Strauss, Jordi McGrath, Nathan White, Donnacha Ryan, Rhys Ruddock, Eoin Reddan, Paddy Jackson, Luke Fitzgerald.
Argentina: Joaquin Tuculet, Santiago Cordero, Matias Moroni, Juan Martin Hernandez, Juan Imhoff, Nicolas Sanchez, Martin Landajo; Marcos Ayerza, Agustin Creevy, Ramiro Herrera, Guido Petti, Tomas Lavanini, Pablo Matera, Juan Martin Fernandez Lobbe, Leonardo Senatore.
Replacements: Julian Montoya, Lucas Noguera, Juan Pablo Orlandi, Matias Alemanno, Facundo Isa, Tomas Cubelli, Jeronimo De La Fuente, Lucas Gonzalez Amorosino.