South American football bosses say accusations questioning the integrity of the Copa America are "unfounded" and "represent a lack of respect".
Argentina captain Lionel Messi claimed the competition was "corrupt" after he was sent off in their 2-1 third-place play-off win over Chile on Saturday.
"The cup's fixed for Brazil," he added.
Messi was shown a red in the 37th-minute against Chile, following a clash with Gary Medel, who was also dismissed.
"We don't have to be part of this corruption," said the Barcelona forward. "They have showed us a lack of respect throughout this tournament.
"Sadly, the corruption, the referees, they don't allow people to enjoy football, they ruined it a bit."
The South American Football Confederation Conmebol later released a statement, which did not directly refer to Messi, saying: "A fundamental pillar of fair play is to accept the results with loyalty and respect.
"It is unacceptable that as a result of incidents typical in competitions, involving 12 teams, all on equal terms, unfounded accusations have been launched that lack the truth and question the integrity of the Copa America.
"These accusations represent a lack of respect for the competition, all the participating players and the hundreds of professionals of Conmebol."
Eight-time champions Brazil face Peru in Sunday's final at 21:00 BST. There will be live text commentary of the game on the BBC Sport website.