"Tests conducted have confirmed that Lionel Messi has a sore left adductor muscle. Both the medical services of FC Barcelona and the AFA (Argentina Football Association) have agreed on this report," Barcelona said in a statement.
"The player will travel to Argentina to join the national team and the evolution of the discomfort will decide his availability to play in the games scheduled."
Argentina sit third in the 10-team South American qualifying group on 11 points from six matches, two points behind leading pair Uruguay and Ecuador.
Edgardo Bauza will take charge of Argentina for the first time when they host Uruguay in Mendoza on Thursday before the side travels to Venezuela for another qualifier in Merida five days later.
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Manchester City striker Sergio Aguero and Paris St Germain midfielder Javier Pastore have already pulled out of the squad through injury, so the 2014 World Cup runners-up will be hoping Messi can be fit enough to play.
Earlier this month, Messi, who has scored 55 goals in 133 appearances for his country, reversed a decision to retire from the national team after they lost the Copa America final to Chile in a penalty shootout at the end of June.
(Reporting by Adriana Garcia; Editing by John O'Brien)
