Sergio Aguero: This is the worst I have seen Lionel Messi
Messi missed Argentina's first penalty as it lost the shootout 4-2 in a repeat of last year's decider against the same opponents, meaning its last three major tournament finals have ended in defeat.
The Barcelona star announced he is set to retire from international soccer, having failed to win any of his four final appearances for his country.
Aguero painted the picture of a broken Messi in the locker room, with Argentina suffering heartbreak for a third consecutive year.
"We are all [depressed], we are trying to think about other things and continue on forward," the Manchester City striker told reporters.
"But it's hard. Once again luck has gone against us.
"Unfortunately, the most broken one is Messi for his missed penalty. It is the worst I have ever seen him in change rooms after the game."