Argentina enacted revenge for their defeat to England in Manchester last week, with a bullying 24-22 win in Salta on Saturday.
Hernandez landed a stream of first-half penalties to compound an early English error at the line-out that led to a simple try for Juan Manuel Leguizamon, with Andy Goode only able to reply with one as the Pumas held their line and their nerve.
That last bit was also important, in the face of some stiff provocation from the English side, whose loss of discipline under presasure will have likely infuriated Martin Johnson more than the result.
Leguizamon’s early try came as a result of two early lost line-outs for England, with Patricio Alabcete and Rimas Alvarez making the intercepts look effortless. From the second, Leguizamon ran a glorious scything line as the rest of his runners drifted, taking him through the gap without a hand being laid on him.
Goode replied with a penalty for England, struck courtesy of an off-the-ball tackle from the otherwise impressive Santiago Fernandez, but it was a brief pause in otherwise one-way traffic. One move, sparked by the effervescent Hernandez, ought to have yielded a second try, but Leguizamon carried the ball too long and ran out of options.
Instead, Hernandez goaled two of a steady flow of penalties resulting from England’s sloppiness at the rucks and another one for a high tackle by Danny Care. He was not the only one to be aiming his shots a little high, Mark Cueto was lucky to stay on the field after 21 minutes.
Hernandez controlled the game with the boot, with his chasers ceaseless in their speed and dilligence at closing down the recipients. The fly-half produvced a mesmeric sequence at one point, with an up and under, a clearance, then a deft grubber to the corner all pulled off within a couple of minutes with awe-inspiring precision.
Half-time was marked with a penalty miss from Goode, then the second half was started by a brilliant Argentina try.
Horacio Agulla steamed through a midfield gap before sending a magnificent 20-yard pass out to Gonzalo Camacho, who showed Harlequins what they will be getting next season with a scintillating sprint finish.
But it was a blip. Whatever Martin Johnson said in the dressing room at half-time, he must have hammered home as he would, say, crashing a fist into a Twickenham desk.
England became the ruthless punishers at the ruck, England dominated the possession, Andy Goode dictated the play with clever kicks.
Goode (Wearing his Nike Laser 2 Rugby boots) chipped away at the lead, 21-6, 21-9, 21-12, 21-15, each penalty coming roughly five minutes after the last, so we headed into the final ten minutes with less than a converted try between the teams, and referee Alan Lewis reminding Ignacio Fernandez Lobbe of the need for discipline.
But cheekily from first phase at a scrum, Hernandez restored a two-score lead with a drop goal.
Cueto dropped a ball on a simple overlap as England threatened and then, after Vesty had come on and added a bit of zip, Delon Armitage’s cheeky flick sent Matt Banahan (Wearing his Adidas Predator powerswerve rugby boots) away down the left and then under the posts to make it 24-22.
But too late. Argentina’s pack marched out the final moments and secured a precious and treasured win.
Tries: Leguizamon, Camacho
Pens: Hernandez 3
Drop goal: Hernandez
Pens: Goode 5
Argentina: 15 Horacio Agulla, 14 Francisco Leonelli, 13 Gonzalo Tiesi, 12 Santiago Fernández, 11 Gonzalo Camacho, 10 Juan Martín Hernández, 9 Alfredo Lalanne, 8 Juan Fernández Lobbe (c), 7 Juan Manuel Leguizamón, 6 Genaro Fessia, 5 Patricio Albacete, 4 Rimas Álvarez Kairelis, 3 Marcos Ayerza, 2 Mario Ledesma, 1 Rodrigo Roncero.
Replacements: 16 Alberto Vernet Basualdo, 17 Juan Pablo Orlandi, 18 Manuel Carizza, 19 Esteban Lozada, 20 Nicolás Vergallo, 21 Miguel Avramovic, 22 Lucas González Amorosino.
England: 15 Delon Armitage, 14 Mark Cueto, 13 Dan Hipkiss, 12 Tom May, 11 Matt Banahan, 10 Andy Goode, 9 Danny Care, 8 Nick Easter, 7 Steffon Armitage, 6 Chris Robshaw, 5 Louis Deacon, 4 Steve Borthwick (c), 3 Julian White, 2 Dylan Hartley, 1 Tim Payne.
Replacements: 16 George Chuter, 17 David Wilson, 18 Ben Kay, 19 James Haskell, 20 Paul Hodgson, 21 Sam Vesty, 22 Mathew Tait.
Referee: Alan Lewis (Ireland)
Assistant referees: Simon McDowell (Ireland), David Changleng (Scotland)
Television match official: Johann Meuwesen (South Africa)
Assessor: Arrie Schoonwinkel (South Africa)