Story highlights Lionel Messi is accused of evading $4.6 million in taxes

Prosecutors say soccer star didn't pay tax owed on money earned from endorsements

(CNN) Soccer superstar Lionel Messi, regarded by many as one of the most talented players in the history of the game, is in court with his father to answer tax fraud charges.

Prosecutors allege the pair sought to hide the Barcelona forward's earnings in offshore accounts, amounting to the defrauding of the Spanish government to the tune of €4.1 million ($4.6 million). They could face a jail term of up to 22 months if found guilty.

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The trial opened Tuesday, but injuries prevented the Argentina star from appearing. He and his father, Jorge Horacio Messi -- who manages his financial affairs -- are only obliged to appear Thursday in order to testify.

Spanish sport newspaper Marca reported that six witnesses, including principals from his former law firm, Juarez and Associates, and an expert have testified in court over the past two days that Messi did not have any knowledge of the contracts that he was signing, and that his father and brother were responsible for the documents.

"The mediator was always Jorge Messi or, occasionally, (his brother) Rodrigo Messi, but it was never Leo," the law firm's Inigo de Loyola Juarez testified.