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.
(BBC)