In-your-face tackling allowed the All Blacks no respite from their loss to Australia last weekend and in a performance that belied their lack of Tests since the last World Cup, the Argentinians were deserving winners.
It was an outstanding display of determination and after all they have been through in a year dominated by Covid-19, it was a monument to their preparation and intent.
Captain and flanker Pablo Matera was outstanding at the breakdown and set the highest of standards for his side and helped Argentina to a 62-42 advantage in rucks won.
The star of their effort, first five-eighths Nicolas Sanchez, who scored all their points, including six penalty goals told the story of the game. The penalties demonstrated the extra pressure the All Blacks put themselves under, but they were also guilty of uncharacteristic mistakes: dropped and inaccurate passes and lineout turnovers.
It continued a pattern of being unable to play their natural game against determined defence that was highlighted by England at last year's World Cup, and continued in the draw and loss to Australia this year.
Coming out after a halftime break where they led 16-3, Argentina continued as they had left off in a dominant first half, but their enthusiasm bubbled over and they were undone by consistent infringing at the breakdown, especially by prop Nahuel Chaparro.
It wasn't until a 50th minute maul infringement by flanker Marcos Kremer that provided the All Blacks with their first try-scoring chance.
From a lineout, out from the Argentina line, the All Blacks threw to the front, and quickly, where No8 Ardie Savea set the maul that moved quickly to the line with skipper and flanker Sam Cane scoring.
However, in spite of the All Blacks' efforts to lift, Argentina reverted to tackling type and maintained the pressure.
Unimpressive as the first half was from the All Blacks with errors at breakdowns, lack of discipline in the face of applied Argentina intensity in defence and mistakes in basics, it was little improved in the second half.
Errors like first five-eighths Richie Mo'unga's direct penalty kick out of touch in-goal just before halftime that robbed New Zealand of their best chance to push for a try that would have made a severe dent in the margin.
In the second half, a likely-looking break from the base of the scrum by replacement No8 Hoskins Sotutu saw him create a gap but instead of taking it he threw a pass which flew well out of the reach of replacement Damian McKenzie and another chance was lost. Another move was shaping by replacement centre Rieko Ioane dropped a pass he would usually catch in his sleep.
Mo'unga played a part in denying Argentina captain and flanker Pablo Matera what would have been an embarrassing try. It came after the All Blacks were caught napping at a midfield break which allowed halfback Tomas Cubelli to run from the base link to the blindside and it was a desperate tackle from halfback Aaron Smith that prevented wing Juan Imhoff from scoring.
But from the ruck Matera charged only to be held up in-goal.
However, in the 18th minute, in a period that saw Argentina put 16 phases together before first five-eighths Nicolas Sanchez chipped to the line and after the ball rebounded off No8 Rodrigo Bruni's knee towards the line, and away from the grasp of All Blacks defenders for Sanchez to pick up and score.
A last-minute try to wing Caleb Clarke was little more than a consolation on a day to forget. The Argentina win has thrown the Tri Nations wide open with each of the sides having a win apiece. Australia play Argentina in Newcastle next weekend and the All Blacks play Argentina in Newcastle in a fortnight.
Scorers:
Argentina 25 (Nicolas Sanchez tries; Sanchez con, 6 pen) New Zealand 15 (Sam Cane, Caleb Clarke tries; Richie Mo'unga con, pen). HT: 16-3