Rafa Nadal issued a statement on Thursday saying he had met all his fiscal obligations after a Spanish website published details about several companies linked to the World No 2 it said had been set up to drastically trim his tax bill.
The website Primeran (www.primeran.com) said the companies had been created with their domicile in the Basque region to take advantage of special tax rules designed to help local firms and had been used to radically cut the amount of tax paid on income from Nadal's image rights.
El Confidencial, another Spanish media outlet, said Basque tax authorities were probing the case. The regional government could not immediately be reached for comment.
Nadal's spokesman published a statement which acknowledged the existence of the Basque companies but said they had now had their domicile transferred to Nadal's native Balearic Islands, where he lives.
"The companies mentioned and the tennis player himself are up to date with the payment of all their tax obligations," the statement said.
"Since the start of his career Rafa has always wanted to maintain his residence in Spain and that's the way it has been, reaffirming his commitment as a Spaniard on, as well as off, the court," the player's agent, Carlos Costa, added.
