Lionel Messi denied having knowledge of the tax issues that led to fraud charges against him, saying Thursday he signed documents without reading them because he trusted his father and the advisers responsible for managing his finances. "I didn't know anything," Messi said while testifying in his tax fraud trial. "I only worried about playing football." Wearing a dark suit and tie, Messi sat alongside his father in front of the judge and listened to other testimony for nearly four hours before being called to testify in the third day of the trial. Speaking for less than 15 minutes, he said he never suspected any wrongdoing when his father would ask him to sign contracts or documents. "I signed what he told me to sign because I trusted my father," Messi said. "I trusted my father, and the lawyers said that I could (sign the documents)." The Barcelona player looked impatient in court at times, looking down and trying to stretch his legs. The left foot that helps him thrive on the soccer fields kept bouncing impatiently underneath the chair. Messi and his father, Jorge Horacio Messi, are facing three counts of tax fraud and could be sentenced to nearly two years in prison if found guilty of defrauding Spain's tax authority of 4.1 million euros ($4.5 million) from 2007-09. They are not likely to face any jail time but could be fined and made to forfeit possible future tax benefits. Both deny wrongdoing, and the money owed was already paid back. The trial is expected to end Friday, and the verdict and sentencing expected next week. Earlier, Messi's father reiterated that his son didn't know the details of his contracts or the structures created in other countries used to handle his income from image rights. "I didn't think it was necessary to inform him of everything," Messi's father said. Hundreds of journalists and a few onlookers were in front of the Barcelona court house when Messi and his father arrived. Authorities had prepared a special operation to control the crowd and protect the player. Some people showed their support to Argentina star, while a few yelled words against him, including asking him to "give the money back" and telling him to "go play in Panama." Messi was also being investigated by Spanish tax authorities after his name was among those released in the probe of international offshore accounts, known as the Panama Papers, although he was not charged for those allegations. Because of the trial, the Barcelona player has missed part of Argentina's preparations for the Copa America, which starts Friday in the United States. The trial is centered on alleged unlawful activities of Messi's father, but authorities said the player knew enough to also be named in the case. Officials said that although Messi was mostly unfamiliar with tax issues, there was sufficient evidence to believe he could have known and consented to the creation of a fictitious corporate structure to avoid paying taxes on income from his image rights. Messi is the latest high-profile player to have to deal with Spain's tough tax system. Neymar, Javier Mascherano, Adriano and Xabi Alonso also were targeted by authorities recently. Mascherano, Messi's teammate with Argentina and Barcelona, earlier this year was handed a suspended one-year prison sentence for not paying nearly 1.5 million euros ($1.6 million) in taxes for 2011-12. Alves to leave Barcelona Roving Brazilian right-back Dani Alves has told Barcelona he intends to leave the club after eight succesful seasons, the Spanish champion confirmed. "He has already told us he intends to leave the club," Barcelona technical director Robert Fernandez said. "We don't like the fact he's going. His behavior on and off the field here has been so exemplary and now he's decided to go. The decision is his and we will respect that," Fernandez told a press conference. Catalan Sports daily Sport claimed Thursday that Alves had already signed with Italian champion Juventus. The 33-year-old international defender is under contract with Barcelona until June 2017 after signing an extension during 2015 at a period where Barcelona was banned from signing new players.