However, CONMEBOL made no mention of Messi's "corruption" accusation against the regional governing body that he made after receiving his red card.
Messi was harshly dismissed in the first half of Argentina's 2-1 win over Chile after a clash with defender Gary Medel.
Television images suggested Messi did nothing wrong as Medel appeared to repeatedly try, unsuccessfully, to headbutt the Barcelona forward.
While most observers acknowledged that the Chile captain deserved to be sent off, Paraguayan referee Mario Diaz de Vivar controversially also gave Messi his marching orders.