At various times in the past, the national teams of Japan, Georgia, Canada, and the United States, plus second-tier representative sides from Australia and New Zealand, have also been involved. Pacific Challenge, which is a competition involving the national "A" sides from Fiji, Samoa, and Tonga (and more recently Junior Japan, Canada A, and Argentina's Pampas XV). Americas Rugby Championship, whose current incarnation involves Argentina's "A" side, currently branded as Argentina XV, and the full national teams of Brazil, Canada, Chile, Uruguay, and the USA.