Backed by a passionate crowd at Estadio Monumental in Buenos Aires, the City striker started from the off as Lionel Scaloni picked the same lineup which began the showpiece final win over France in last December.
La Arana was looking to add to tally of five international goals, four of which came at the tournament in Qatar, but despite a dominant first-half display the scoreline remained goalless going into the interval.
Scaloni then rang the changes during the break which saw our forward replaced by Inter Milan’s Lautaro Martinez in leading the line.
The party then reached fever pitch when Atlanta United’s Thiago Almada opened the scoring with with 11 minutes remaining, tapping home a rebound after Lionel Messi’s initial effort was saved.
Argentina’s talismanic captain then stepped up to seal the victory with a sublime free-kick on the cusp of full-time which sealed his 800th career goal for club and country.
Following the final whistle, Alvarez and his teammates were presented with their own replica World Cup trophies in a spectacular ceremony to celebrate their achievement in Qatar.
Elsewhere, City youngster Alex Robertson earned his maiden Australia cap in the Socceroos’ 3-1 win over Ecuador.
The versatile midfielder came from the bench with 30-minutes remaining of the friendly at the CommBank Stadium in Parramatta.
By doing so, he followed in the footsteps of his father and grandfather in representing Australia - becoming a third-generation Socceroo.
St Pauli’s Jackson Irvine’s opening goal was cancelled out Felix Thomas’ strike, before Awer Mabil restored Graham Arnold’s side’s lead before half-time.
And Garang Kuol extended their lead further on the cusp of the final whistle following a dogged second-half display.
