Argentina have made three changes in the forward pack for Saturday's Rugby Championship clash against South Africa at Santiago del Estero as they seek to keep alive their hopes of winning this year's competition.

Pedro Rubiolo returns to the second row after missing their runaway 67-27 triumph over Australia in Santa Fe a fortnight ago because of concussion and will be partnered by Franco Molina with the veteran pair of Tomas Lavanini and Guido Petti making way.

Petti will be among the replacements, the Argentina Rugby Union announced on Thursday.

Joaquin Oviedo was rewarded for coming off the bench against the Wallabies and scoring two tries in Santa Fe and will play at No.8 as Juan Martin Gonzalez shifts to the substitutes' bench.

The uncapped tighthead prop Pedro Delgado, 26, is on the bench for the first time, in place of Eduardo Bello, who tore the anterior cruciate ligament in his right knee after coming on against Australia in the Puma's last test.

Veteran winger Matias Moroni is also among the replacements after returning from a hip injury that saw him miss the last two clashes in the Rugby Championship.

Argentina are eight points adrift of leaders South Africa in the standings and must win on Saturday to keep alive any chance of catching the Springboks, who have won all four of their games in this year's tournament.

Argentina have 10 points after wins over Australia and New Zealand but they were also beaten once each by the All Blacks and Wallabies.

ARGENTINA: Juan Cruz Mallia, Bautista Delguy, Lucio Cinti, Santiago Chocobares, Mateo Carreras, Tomas Albornoz, Gonzalo Bertranou, Joaquin Oviedo, Marcos Kremer, Pablo Matera, Pedro Rubiolo, Franco Molina, Joel Sclavi, Julian Montoya (capt), Thomas Gallo. Reserves: Ignacio Ruiz, Ignacio Calles, Pedro Delgado, Guido Petti, Juan Martin Gonzalez, Gonzalo Garcia, Santiago Carreras, Matias Moroni.