Spanish prosecutors have accused Real Madrid midfielder Luka Modric of defrauding tax authorities of €870,728 in 2013 and 2014, Marca have reported.
Prosecutors have claimed that they were informed last month that the Croatia international might have "financial positions" on the Isle of Man.
These were not known by tax authorities and could have had an impact on the total amount of tax Modric paid in Spain.
The 32-year-old's wife, Vadja, has also been accused of tax irregularities following the revelations.
The Prosecutor's Office have taken action against Modric just one day after his Real Madrid teammate Marcelo appeared in court as part of another tax case.
The Brazilian full-back is accused of defrauding authorities of €490,917.70 by using companies abroad to handle his earnings from image rights.
Los Blancos are not the only club to have been targeted by Spanish authorities in recent weeks.
Lionel Messi and his father were last year found guilty on three counts of defrauding tax authorities of €4.1m from image rights income.
Cristiano Ronaldo, Ricardo Carvalho, Angel Di Maria, Javier Mascherano, Radamel Falcao and Fabio Coentrao are also under investigation.
Nor is it restricted to players; former Real Madrid and current Manchester United manager Jose Mourinho has also found himself embroiled in investigations from Spanish authorities.