Former Australia coach Michael Cheika will work with Argentina for the rest of 2020, pitting him against the Wallabies in the Rugby Championship.
He has been hired as an "external advisor" to the Pumas.
Head coach Mario Ledesma said Cheika would bring "a lot of experience" to his set-up.
Ledesma has previously worked under Cheika as part of the Australia coaching staff that reached the 2015 Rugby World Cup final and at French side Stade Francais.
"We have already had several discussions with him and all the staff about the game, defence, attack, types of exercises, individual techniques," said Ledesma.
"The exchange has been spectacular."
He added that Cheika's local knowledge was also useful for an edition of the Rugby Championship that will take place entirely in Australia.
"We were able to talk and listen to his recommendations about places to train, schedules and even issues related to the weather," Ledesma added.
Cheika, whose previous union roles include a five-year stint at Leinster, had recently been working as a skills coach at rugby league side Sydney Roosters.
Argentina, who have finished bottom of the Championship for the past four years, begin this year's tournament with a match against South Africa in Brisbane on 7 November.