Cubelli called in to face Wallabies
Cubelli, who plays Super Rugby for the Brumbies, has played 32 of his 51 Tests off the bench.
Cubelli is one of four changes to the starting line-up – with Juan Manuel Leguizamon, Santiago González Iglesias and Lucas Gonzalez Amorosino also coming in.
Guido Petti and Juan Martin Hernández both suffered injuries against New Zealand last week.
Iglesias replaces Hernández at inside centre alongside Matias Moroni, who moves in from the wing to complete the midfield partnership.
Amorosino comes in for Moroni out wide, while centre Matias Orlando drops to the bench.
Javier Ortega Desio, who stood in for Leguizamon in the back row last week, moves to lock in place of Petti.
Gabriel Ascarate is in line for his Test debut, having been named on the bench.
The Pumas and Wallabies have met 25 times, with 19 wins for the Wallabies, five victories for Los Pumas and one draw October 31, 1987, in Buenos Aires.
It will be the second time the two teams meet in Perth, with the Wallabies having won 14-13 in September 2013.
The players in the current squad who featured in that encounter are Agustín Creevy, Nicolas Sanchez, Tomas Cubelli, Lucas Gonzalez Amorosino, Martin Landajo, Pablo Matera and Juan Manuel Leguizamón.
Wallabies coach Michael Cheika feels Cubelli's "inside" knowledge of the Wallaby players may assist the visitors.
"Cubelli we know," Cheika said, adding: "[He is] obviously a great player.
"I'm sure they have given him that start so he can stick it to his Aussie colleagues," Cheika added.
Cheika said Iglesias and Hernández are both strong defenders, and called Leguizamon, whom he coached at Stade Francais, a "class player".
"They're going to be very mobile and I'd suggest there'd be a lot of running in this game. The ball's going to move around a fair bit."
Argentina: 15 Joaquin Tuculet, 14 Santiago Cordero, 13 Matias Moroni, 12 Santiago Gonzalez Iglesias, 11 Lucas Gonzalez Amorosino, 10 Nicolas Sanchez, 9 Tomas Cubelli, 8 Facundo Isa, 7 Juan Manuel Leguizamon, 6 Pablo Matera, 5 Matias Alemanno, 4 Javier Ortega Desio, 3 Ramiro Herrera, 2 Agustin Creevy (captain), 1 Nahuel Tetaz Chaparro.
Replacements: 16 Julian Montoya, 17 Lucas Noguera, 18 Enrique Pieretto, 19 Marcos Kremer, 20 Leonardo Senatore, 21 Martin Landajo, 22 Gabriel Ascarate, 23 Matias Orlando.
Date: Saturday, September 17
Venue: nib Stadium, Perth
Kick-off: 18.05 (20.05 AEST; 07.05 Argentina time; 10.05 GMT)
Referee: Wayne Barnes (England)
Assistant referees: Nigel Owens (Wales), Nick Briant (New Zealand)
TMO: Ben Skeen (New Zealand)
