A last-minute penalty goal was all that separated the touring NSW Barbarians rugby side from an experienced Argentina team in the first of two matches.
The Pumas snatched victory with the last kick of the game from Nicolas Sanchez after being outscored four tries to three by a team mostly comprising frontline NSW Waratahs players in La Planta on Saturday.
Two tries by Wallabies prop Sekope Kepu tries at either end of the first half gave the visitors a two-point advantage going into the break.
That lead was extended just six minutes into the second period when wing Peter Betham crossed for NSW's third try.
When fullback Drew Mitchell added another on the 60 minute mark, coach Michael Cheika's side looked like taking a big scalp against a fully-capped Test outfit.
Hoever the hosts came back with two tries within four minutes from replacement hooker Agustin Creevy.
With Sanchez and Bernard Foley exchanging penalty goals in the closing 10 minutes, the NSW Barbarians led by a single point going into the final seconds.
Having gained useful experience from playing against their Rugby Championship opponents, NSW's national squad contingent fly back to Australia to join the Wallabies training camp in Sydney.
The remaining squad members get another crack at Argentina on Friday at Estadio Padre Martearena in Salta.
