US down Argentina to open Americas defence
The contest went down to the wire, as a last-gasp attack from Argentina saw Rodrigo Bruni cross the line only to knock on.
Juan Cappiello was shown yellow in just the seventh minute for a late tackle on Marcel Brache.
Will Magie couldn't connect on the penalty, but landed his second attempt to put the Americans up 3-0.
Argentina fought their way back into it with a penalty from Juan Cruz Gonzalez and a try from Santiago Montagner who powered over with the man advantage with Cam Dolan in the sin bin.
The conversion was good to put Argentina up 10-3 at half-time, but the hosts dominated after the break.
Magie closed the gap with his second penalty and the Eagles got a try as Tony Lamborn ripped through two defenders to sweep around the corner and regain the lead for the United States.
With both teams looking to their replacements, former England Under-20 flyhalf Will Hooley came on for Magie to make his first appearance in an Eagles jersey and slotted two penalties to make it 17-10.
A desperate Argentina looked to have produced the try they needed, but Bruni lost possession of the ball before the grounding and upon video review the try was waved off.
In the day's other match, Brazil edged Chile 16-14 in Santiago, their first victory ever on Chilean soil.
Jardel Vettorado dived over for a try for Brazil and Josh Reeves contributed the conversion and three penalties as Brazil posted their first away win in ARC play.
The tournament continues next weekend, when Brazil host Uruguay at Sao Paulo, Argentina XV host Chile at Ushuaia and the United States host Canada in Sacramento, California.
Agence France-Presse
