The captain rounded off a 3-1 win over the Guarani with an immaculate strike from distance, and also praised the atmosphere in Cordoba as the side pick up another victory
The Barcelona star twice hit the woodwork during a 3-1 triumph in Cordoba's Estadio Mario Kempes, but he finally registered in the second half with a stunning free kick to guarantee victory. Angel Di Maria and Gonzalo Higuain also struck for the Albiceleste, who now lead Chile and Ecuador by one point in the race to Brazil 2014.
Messi took the opportunity to thank the crowd in Cordoba, which was also the venue for Argentina's sole victory of the 2011 Copa America - over Costa Rica - and where the fans were vocal in their praise for the star.
"This is a beautiful feeling. It is incredible when the fans give you so much affection. The same happened to me in the Copa America, in Cordoba and in Buenos Aires," 'La Pulga' told reporters after the match.
And the No.10 also advised calm ahead of a potentially tricky visit to Lima on Tuesday, stating that Peru would prove tough opposition.
"This triumph is very valuable, now we go to Peru, who are a very difficult team to play against.
"Leading the group is the least important aspect, the key is to keep gaining confidence as a group."
Messi has now scored nine goals in five international appearances during 2012, all of which have been won by Argentina.