Buenos Aires - The Jaguares survived a yellow card and several late Brumbies onslaughts to win 20-15 in Buenos Aires on Saturday and complete a Super Rugby hat-trick.
A deserved, hard-earned round 11 success at Estadio Jose Amalfitani came after they defeated the Bulls and the Sharks on a tour of South Africa.
Victory lifted the Argentine outfit five places to sixth in the combined standings of the southern hemisphere club championship and to third in the South African Conference.
The Australians also came into the match on the back of two victories over South African opposition, the Lions and the Stormers.
They were in with a chance of winning right to the end of a match that contrasted sharply with the last between them in Buenos Aires - a 39-15 triumph for the Brumbies two years ago.
It was tense affair in perfect conditions for rugby with never more than seven points between two evenly matched sides.
The Jaguares turned around a seven-point deficit midway through the opening half to lead 17-15 at half-time.
There was only one addition to the score in the second half, a penalty slotted by Argentine flyhalf Domingo Miotti on 62 minutes.
The Canberra outfit must have fancied their chances when the hosts were temporarily reduced to 14 men with the sin-binning of loose forward Marcos Kremer after 66 minutes.
Several times the visitors forced lineouts five metres from the Jaguares' tryline, but they could not force their way over.
Defeat keeps the Brumbies 12th overall and third in the Australian Conference, four points behind the pacesetting Melbourne Rebels.
Both teams were guilty of handling errors at crucial moments, with the Argentines the slightly more frequent offenders.
But the home side were less prone to mistakes in the crucial closing stages, defending heroically to thwart the Brumbies.
"This was a wonderful performance by all our players - the starting 15 and the replacements who came on in the second half," said Jaguares skipper Jeronimo de la Fuente.
"I believe we deserved the victory, particularly because of our bravery in defence when reduced to 14 men for 10 minutes in the closing stages."
Sebastian Cancelliere and Folau Fainga'a exchanged early tries before the impressive Tom Banks went over and Christian Lealiifano converted to give the Brumbies a 12-5 advantage.
Stung by conceding two tries within 20 minutes, the Jaguares scored two in just three minutes, first through Matias Orlando and then Agustin Creevy.
Miotti, who debuted in Super Rugby this month, converted one before
an additional time penalty from Lealiifano closed the first half
For all the second half endeavour from both sides, there was only one further score as Miotti slotted a penalty to compensate for two missed conversions.
Tries: Sebastian Cancelliere, Agustin Creevy, Matias Orlando
Conversion: Domingo Miotti
Tries: Tom Banks, Folau Fainga’a
Conversion: Christian Lealiifano
15 Emiliano Boffelli, 14 Sebastian Cancelliere, 13 Matias Orlando, 12 Jeronimo De La Fuente (captain), 11 Santiago Carreras, 10 Domingo Miotti, 9 Tomas Cubelli, 8 Tomas Lezana, 7 Marcos Kremer, 6 Pablo Matera, 5 Tomas Lavanini, 4 Guido Petti Pagadizaval, 3 Santiago Medrano, 2 Agustin Creevy, 1 Nahuel Tetaz Chaparro
Substitutes:16 Julian Montoya, 17 Mayco Vivas, 18 Enrique Pieretto Heilan, 19 Rodrigo Bruni, 20 Javier Ortega Desio, 21 Felipe Ezcurra, 22 Bautista Ezcurra, 23 Juan Cruz Mallia
15 Tom Banks, 14 Henry Speight, 13 Tevita Kuridrani, 12 Tom Wright, 11 Toni Pulu, 10 Christian Lealiifano, 9 Matt Lucas, 8 Pate Samu, 7 Tom Cusack, 6 Jahrome Brown, 5 Sam Carter, 4 Rory Arnold, 3 Allan Alaalatoa, 2 Folau Fainga’a, 1 James Slipper
Substitutes:16 Connal Mcinerney, 17 Scott Sio, 18 Leslie Leuluaialii-Makin, 19 Darcy Swain, 20 Murray Douglas, 21 Joe Powell, 22 Irae Simone, 23 Andy Muirhead