Cardiff - Two-try hero Juan Imhoff said Argentina's ferocious defence was as important as their attacking intent in the emphatic 43-20 victory over Ireland in the Rugby World Cup quarter-finals on Sunday.
The Pumas roared into a 17-0 lead following two early tries
Argentina will play Australia or Scotland in the last four.
"We will enjoy this moment but we know we have a tough game next week," winger Imhoff told ITV.
"Ireland played with a great intensity. We are a really good team in offence. But today we had a defence to make the difference."
Ireland, decimated by injuries and suspensions, simply ran out of steam at the Millennium Stadium.
"It's very disappointing to lose in such a big game. We didn't help ourselves at the start. We came back into it but we gave ourselves too much to do. This is a special group of players and a special group of fans," stand-in captain Jamie Heaslip said.
"Argentina played a very expansive game. They stretched us. They took their chances. We got back to within three points -- but then they took their opportunities to kick on."