His hat-trick in a remarkable 4-3 friendly win over arch-rivals Brazil in New Jersey on Saturday took his tally for the national side to 26 goals in 70 matches and he saved the best until last.
His third goal, six minutes from time at Meadowlands Stadium, was a classic sealed with a trademark run and unstoppable shot into the top corner of the goal from outside the penalty area.
He never played first division football in Argentina, having moved to Barcelona in his early teens, but fans were forgetting that he helped his country's under-20s win the World Youth Cup in 2005.
He is now Argentina's fourth highest scorer behind Gabriel Batistuta (56), Hernan Crespo (35) and Diego Maradona (34) with potentially another decade in front of him in top class football.
"Luckily [Messi] is Argentine and we can enjoy him," said coach Alejandro Sabella.
"He's been going through great moments for quite some time, he won the last three Ballons d'Or in Europe and he's delighting us with great performances.
"We try to play a different game from Barcelona, more vertical, because we don't have the Barcelona players to play their game," Sabella said by way of explaining that Messi is finding his place and style in the Argentina team.
Making Messi captain may have been the key, Sabella having done so as soon as he took charge last August following Argentina's disappointing Copa America on home soil.
Messi scored a crucial equaliser in a 2-1 away win over Colombia in a qualifier in November and followed that with his first hat-trick in February's friendly 3-1 away win over Switzerland.
