Today is Lionel Messi's 26th birthday. But from the sound of things, he is not having the best birthday of his life. That's because, according to the La Vanguardia newspaper in Spain, the Barcelona striker just handed over $13.1 million to Spanish tax authorities in order to pay off a tax debt that he racked up thanks to his 2010 and 2011 tax returns. And that might not be the only money he hands over to the tax authorities, either.

Last week, Messi was accused of tax fraud in Spain. According to the tax authorities there, Messi and his father Jorge Horacio filed fraudulent tax returns in 2007, 2008, and 2009 and owe the Spanish government more than $5 million. So the $13.1 million that he just paid might be just a fraction of what he actually owes. Messi has denied any tax fraud, though, and it's widely believed that he may seek some sort of deal with the Spanish tax authorities that would allow him to settle his tax issues once and for all.

But for now, Messi is out $13.1 million. It's not exactly the best way to spend a birthday. But hey, it sure beats jail time, right?

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[via ESPN FC]