Messi was named as part of Sergio Batista's 18-man squad to contest the games in Beijing next month and as such was summoned to Japan for pre-tournament training.
Barcelona declined to send the youngster, stating that the Olympics were not a full FIFA contest and thus his attendance was not mandatory: they would rather keep him for the Champions League qualifiers.
FIFA president Blatter, however, stated in a letter to 205 national associations today that such actions were against the "spirit" of the games that clubs were "obliged" to release players who, like Messi, are under 23.
But Marca claims that Barça have no intention of acting just let. The letter was sent to the RFEF (Spanish FA), not their club; this, coupled with the face that the European Club Association (ECA) is sticking to its guns, has emboldened them.
The ECA stated today that as the tournament is still not part of the harmonised international calendar, Blatter's words have no official weight.
The LFP (Spanish professional league system), having been alerted to Blatter's standpoint by the RFEF, are also willing to take Barcelona's side on this issue.
The club themselves have yet to formally comment since Blatter's words came to light, although they have published on their official website notices relating to the LFP and ECA standpoints.
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