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The 1951 South American Rugby Championship was the first edition of the two tiered competition of the leading national Rugby Union teams in South America.
The tournament was arranged by the "River Plate Rugby Union" (currently "Argentine Rugby Union"). In February 1951 a match was organized in Buenos Aires, the first edition of Pan American Games, but it was not possible to arrange a tournament of rugby for those games, so a "Torneo Internacional" was arranged in September. Initially this competition was called Torneo Internacional ABCU using the initials of the countries participating
After the 1958 edition, this tournament was recognized as the first edition of the competition.
Argentina
Brazil
Chile
Uruguay