New Zealand battled past a determined Argentina to set up a plum World Cup semi-final against arch-rivals Australia.
The All Blacks struggled to assert their expected dominance in the first half as Julio Farias Cabello's try gave the underdogs a shock lead.
But seven penalties from Piri Weepu slowly squeezed the life out of the Pumas before tries from Kieran Read and Brad Thorn made the quarter-final safe.
The win for Graham Henry's men was marred by an injury to fly-half Colin Slade, himself the replacement for injured star man Dan Carter.
Slade, who suffered a groin injury as he attempted to offload out of the tackle, was replaced after 33 minutes by 22-year-old Aaron Cruden.
Slade had ceded place-kicking duties to team-mate Weepu from the start, and the scrum-half was on target with two penalties to put the home side 6-0 up midway through the first half.
The lumbering Read thought he had scored in the left-hand corner, only to be denied by the television match official after Santiago Fernandez's desperate covering tackle.
Felipe Contepomi missed a kickable penalty of his own, but the Pumas then stunned a packed Eden Park with a wonderful breakaway score.
Leonardo Senatore rampaged off the base of a scrum and tore through the Kiwi rearguard before feeding Contepomi, who flipped on a pass to his supporting runners.
While the All Black defence scrambled to haul down the charge just short of the line, flanker Cabello burrowed over to make it 6-5 before Contepomi slid over a delight of a conversion from the touchline for 7-6.
Weepu calmed a shocked home support with two simple penalties after Argentine infringements in the ruck to give the World Cup favourites a 12-7 lead at the interval, but it was far from the stroll many home supporters had expected - and the first time the All Blacks had failed to score a first-half try in a World Cup match in 12 years.
Marcelo Bosch added to Kiwi nerves by battering a penalty over from the halfway line before Weepu replied from the 22-metre line for 15-10.
The absence of both Carter and Slade left the usually rapier-like All Blacks back line uncharacteristically blunted, with Sonny Bill Williams snagged as he raced down the left touchline.
The Argentine defence was immense, replacement centre Juan Jose Imhoff sprinting across to put Cruden into touch after Weepu's cute cross-kick.
But the relentless physical effort was taking its toll. On the hour Weepu added another three points from bang in front after scrum-half Nicolas Vergallo was sin-binned for persistent infringement to extend the lead past a converted try.
Read combined with skipper Richie McCaw before Cruden was gobbled up with Conrad Smith ready to pounce, while Argentina's sole threat was a lovely dummying dancing run from full-back Martin Rodriguez stepping up to first receiver.
But the blue-and-white line was being stretched, and after a series of drives under the Argentine posts Weepu spread the ball out left to find Read on the charge again, and this time he would not be denied.
The 13-point cushion gave New Zealand room to finally play with freedom, and the offloads began to find hands and the running lines big holes in the Argentine defence.
At the death Thorn crossed for a second try after a break from Jimmy Cowan and clever pass inside from Cory Jane to add gloss to the scoreline and set up a repeat of the World Cup semi-final of 2003.
New Zealand: Muliaina, Jane, Smith, Nonu, SB Williams, Slade, Weepu; Woodcock, Mealamu, O. Franks, Thorn, Whitelock, Kaino, McCaw, Read.
Replacements: Toeava for Muliaina (40), Cruden for Slade (33), Hore for Mealamu (65), A. Williams for Whitelock (62), Cowan for Weepu (72), Afoa for Franks (78), Vito for McCaw (78).
Argentina: Rodriguez, Camacho, Bosch, Contepomi, Agulla, Fernandez, Vergallo; Roncero, Ledesma, Figallo, Carizza, Albacete, Farias Cabello, Leguizamon, Senatore.
Replacements: Jose Imhoff for Agulla (50), Lalanne for Vergallo (49), Ayerza for Roncero (39), Creevy for Ledesma (70), Scelzo for Figallo (59), Campos for Carizza (62), Amorosino for Rodriguez (68).
Sin Bin: Vergallo (58).