The Barcelona and Argentina football star, Lionel Messi, who is on trial for alleged tax fraud in Spain, has told a court he had no involvement in the management of his financial affairs.

"I was playing football, I knew nothing," he said.

Messi and his father Jorge, who manages his finances, are accused of defrauding Spain of €4.1m (£3.2m; $4.6m).

The authorities allege that the two used tax havens in Belize and Uruguay to conceal earnings from image rights.

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.

Messi, 28, said he signed documents without reading them because he trusted his father and the advisers responsible for managing his finances.

"I only worried about playing football," he told the judge.

Speaking for less than 15 minutes, he said he never suspected any wrongdoing when his father would ask him to sign contracts or documents. Jorge Messi also denies the charges.

Spain's tax agency is demanding heavy fines and prison sentences.

The trial began on Tuesday, and Thursday is expected to be the final day. A verdict is not expected until next week.

Because of the trial, Messi has missed part of his national team's preparations for the Copa America, which starts on Friday in the US. Argentina's first game is on Monday.

Evidence is being considered regarding income related to Messi's image rights, including contracts with Banco Sabadell, Danone, Adidas, Pepsi-Cola, Procter and Gamble, and the Kuwait Food Company.

Messi's lawyers had argued that the player had "never devoted a minute of his life to reading, studying or analysing" the contracts.

But the high court in Barcelona ruled in June 2015 that the football star should not be granted immunity for not knowing what was happening with his finances, which were being managed in part by his father.

Messi and his father made a voluntary €5m "corrective payment", equal to the alleged unpaid tax plus interest, in August 2013.

The footballer is the five-time World Player of the Year and one of the richest athletes in the world.