France-based Argentina players have been permitted to play for the national team in a Test against South Africa in August.
The match against the 2007 world champions will go ahead on August 9 in Johannesburg as part of a series of events for Nelson Mandela's 90th birthday.
The South African Rugby Union invited the Argentinians months ago but they were not able to confirm because the Springboks wanted to face the strongest side possible, which depended on the cooperation of French league as most of the Pumas play there.
"It's an honour for us to be part of such an important event," said Argentinian Rugby Union president Porfirio Carreras.
"Having the possibility to add this Test to our calendar, against the reigning world champions and with the possibility of counting on the France-based players, is a very important achievement."
Argentina will want to exact revenge for last year's World Cup semi-final which the Springboks won 37-13 in October.
Newly-appointed head coach Santiago Phelan is delighted with the fixture.
"It is a very important match because of what South African rugby represents all around the world," he said.
"We'll see how we can plan training sessions with players abroad, as they will be resting after the end of the different seasons.
"However, we'll approach this Test very seriously and be trying to go on improving things."
Phelan, assisted by Fabian Turnes, will make his debut as Marcelo Loffreda's successor on June 7 against Scotland in Rosario, before meeting Frank Hadden's side once more in Buenos Aires a week later.