Argentina will make their Four Nations debut against South Africa next August, the Independent on Sunday has learned.
The Pumas will join the Springboks, New Zealand and Australia in the expanded tournament, with the August date forming the start of an eight-week schedule of home-and-away fixtures among the four teams.
That switch - the old-style Tri- Nations was played in June and July - clashes with the start of the English and French club seasons.
The International Rugby Board has already stepped in to force European clubs to release Argentinian players for six weekends in those eight weeks.
But English clubs are concerned at the potential impact on their contracted players. Representatives of Premiership Rugby will meet with the Argentinian Union in Auckland on October 17.