Messi already served one match of the four-match ban that was imposed when the FIFA disciplinary committee gave its ruling hours before Argentina's 2-0 loss in Bolivia in March.
FIFA said its appeal committee considered Messi's behavior “reproachable” for verbally abusing a linesman late in a 1-0 win over Chile on March 23. But the panel concluded the “evidence available was not sufficient to establish to the appropriate standard” required for the disciplinary committee to impose the initial suspension.
“The appeal committee nevertheless underlines the importance of always showing respect to the match officials, stressing that such a principle is essential in football and any unsporting conduct that may be contrary to the principles of fair play cannot be accepted,” FIFA said in a statement.
Argentina's next World Cup qualifier is at Uruguay on Aug. 31.
Argentina is fifth in the 10-team South American group with four games left. The 2014 World Cup runner-up is in line to advance to a November playoff against a team from Oceania, likely to be New Zealand.