Bartomeu says the club stands behind the Argentine as Spanish tax problems continue to haunt their star.
"Messi is more than goals and titles, he represents the spirit of a young player who arrived at the La Masia, our grassroots and grew with the club.
"Messi's value for Barca is unlimited. He came to our club when he was 13 and has just turned 27.
"He's one of ours."
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