The Barcelona star was red-carded during Argentina’s 2-1 victory over Chile in the third-place play-off on July 6 after getting into a scuffle with Gary Medel.
He did not attend the ceremony to pick up his medal, and the Argentina captain alleged that the tournament had been fixed in favour of hosts Brazil, who beat Argentina in a controversial semi-final on their way to the title.
Messi was handed a one-match ban and a $1,500 fine for his sending off last month.
CONMEBOL had said that the Barcelona forward’s comments were “unacceptable”.
Messi has seven days to appeal his suspension. If unsuccessful, he will miss upcoming international friendlies against Chile, Mexico and Germany in September and October.
(Production: Stefan Haskins)