Ireland overcame a nervy first-half to run out 29-17 winners over an under-strength Argentina in the first rugby Test on Saturday.
The Six Nations champions scored tries through Chris Henry, Jonny Sexton and Andrew Trimble, Sexton kicking a conversion and two penalties, the latter feat matched by his replacement Ian Madigan.
Manuel Montero scored a memorable try for the under-strength Pumas, Nicolas Sanchez adding a conversion and penalty before Tomas de la Vega crossed for a late consolation try converted by Santiago Gonzalez Iglesias.
The Irish were guilty of trying to play too much rugby in their own half against a spirited Argentina side missing the bulk of their foreign-based players and comprising mainly second-stringers.
The teams meet again next week in Tucuman.