CARDIFF, Wales (AP) -- Argentina pushed into an early 17-point lead and produced a late flourish to beat Ireland 43-20 in the Rugby World Cup quarterfinals on Sunday, reaching the last four for only the second time.
The Pumas set up a semifinal against either Australia or Scotland after scoring two tries in each half at Millennium Stadium, with winger Juan Imhoff -- a star of the tournament -- crossing either side of the break.
The other tries came from center Matias Moroni and fullback Joaquin Tuculet, providing more evidence that Argentina is no longer just reliant on its traditional strength in the forwards.
Flyhalf Nicolas Sanchez kicked 23 points, missing just one of his 10 shots at goal.
The injury-hit Irish, who have still never reached the semifinals despite a rich rugby history, will rue a slow start when they fell behind 17-0 after 14 minutes, and then 20-3 after 22 minutes.
It's the third time they have been eliminated from a World Cup by Argentina, and another blow for the northern hemisphere, after losses for Wales and France on Saturday. Scotland is a big underdog against the Wallabies, too.
Ireland will point to the absence of captain Paul O'Connell, star flyhalf Johnny Sexton and influential flankers Sean O'Brien and Peter O'Mahony as big factors behind their loss, but improving Argentina would have been a tough opponent regardless.
The Pumas' four seasons in the Rugby Championship has made the team to produce a better all-round game, and they demonstrated that in the first 15 minutes when an indisciplined Ireland was blown away by some backline brilliance.
Sanchez was the heartbeat, interchanging with center Juan Martin Hernandez at first receiver and playing flat to cause the Irish defense problems.
From a Sanchez bomb in the third minute, Tuculet leapt highest and set up a phase that ended with winger Santiago Cordero putting in Moroni for a try in the right corner.
The second try came down the right, too, as Cordero ran into space and kicked on. Imhoff was the quickest of three Argentine chasers and managed to collect and ground before the dead-ball line for his fourth try in this tournament.
When Sanchez booted a 14th-minute penalty for 17-0, the Irish needed to produce the greatest comeback in World Cup history -- and a yellow card three minutes later to Argentina prop Ramiro Herrera gave them hope.
Ian Madigan and Sanchez traded penalties before Robbie Henshaw's pick-up-and-pass set free Luke Fitzgerald, on as an injury replacement for Tommy Bowe, to cut inside on the left wing and score a try converted for 20-10 at halftime.
The next score was crucial and it went to Ireland in the 44th, with Fitzgerald again providing the cutting edge. He made a break through the middle and delivered a perfect offload that Jordi Murphy charged onto and over the line.
Sanchez and Madigan booted penalties and Ireland was only 23-20 behind with 20 minutes left. But many of Argentina's top names have had two weeks of preparation for this match, after being rested for the final pool game, and their superior fitness told near the end as Tuculet and Imhoff burst through for converted tries.