A Spanish judge has summoned Barcelona footballer Lionel Messi to appear in court on 17 September over tax fraud allegations.
The 25-year-old Argentine, who has four times been named World Player of the Year, and his father are accused of defrauding the Spanish authorities of more than 4m euros (£3.4m).
They are suspected of using companies abroad - in Belize and Uruguay - to sell the rights to use Messi's image.
They both deny the allegations.
Messi's net salary from Barcelona is said to be about 16m euros a year, making him one of the world's most highly-paid sportspeople.
He has also signed multi-million-dollar endorsements with commercial sponsors around the world.
The player and his father, Jorge, are accused of three times defrauding the Spanish state of taxes.
The income related to his image rights included contracts with Banco Sabadell, Danone, Adidas, Pepsi-Cola, Proctor and Gamble and the Kuwait Food Company.
If he is convicted, Messi could face up to six years in prison and a big fine, according to Spain's Efe news agency.
He wrote on his Facebook page, after the allegations became known last week: "We have never committed any infringement. We have always fulfilled all our tax obligations."
Messi's achievements on the field have made him one of the most marketable in the business.
He came from a modest background and has overcome a serious health issue, joining Barcelona as a 13-year-old in 2000 and making his first-team debut only three years later.
He was ranked 10th among Forbes' list of sports stars' incomes this month.
The president of Barcelona FC, Sandro Rosell, has said the club has no doubt that the superstar is innocent of tax avoidance.
Messi is due to play a prominent role in the Adidas World Cup marketing campaign.
Adidas CEO Herbert Hainer told reporters that the company "will continue to work with Lionel. He's the best football player in the world and we are happy that we have him".
But the allegations are a big blow to the prestige of Messi, who has long been seen as a more humble figure than most top-class footballers.