Nicolas Sanchez, Matias Moroni and Santiago Cordero scored two tries apiece as a rampant Argentina thrashed an inexperienced Japan 54-20 to open the international window in style on Saturday.
Sanchez also kicked three penalties and five conversions for a personal tally of 29 points. Replacement scrumhalf Tomas Cubelli scored Argentina's seventh try six minutes from time.
Japan, featuring 13 uncapped players in the matchday 23 in coach Jamie Joseph's first game in charge since taking over from Eddie Jones, scored consolation tries through number eight Amanaki Lelei Mafi and debutant winger Lomano Lemeki.
Flyhalf Yu Tamura converted both and kicked two penalties, including the one that opened the scoring and gave the hosts a fifth-minute lead at the Prince Chichibu Memorial Stadium.
That was as good as it got for the Brave Blossoms as Sanchez and starting scrumhalf Martin Landajo orchestrated the up-tempo attacking style that has typified the Pumas' play this season and the bruising Argentine pack took control.
Winger Moroni and Sanchez crossed to help give the visitors a 21-6 lead at the break and Cordero, on the other wing, got his first try at the end of a sweeping move soon after the break.
Japan stunned the Springboks at last year's Rugby World Cup but were always going to struggle with so many new faces against a hardened Pumas side which has already played New Zealand, South Africa and Australia twice this year.
Mafi, one of the few forwards remaining from the World Cup campaign, barged over from the base of a ruck after 52 minutes, before Lemeki, a standout in Japan's stunning Olympic sevens campaign, ran in a brilliant individual effort at the death.
Japan next head to Tbilisi to face Georgia before rounding out their November campaign with matches against Wales in Cardiff and Fiji in Vannes, France.
Argentina also head to Europe where they are sure to face tougher matches in Wales, Scotland and England.
