Real Madrid has exercised the option of signing Sao Paulo loanee Casemiro on a permanent deal, Brazilian media reported on Thursday.

The 21-year-old joined the Spanish giants on loan in January and made his Liga debut in a 3-1 victory over Real Betis at the Santiago Bernabeu on April 19.

A series of impressive performances for Real Madrid Castilla in Spain's second tier convinced club president Florentino Perez to make Casemiro'smove a permanent one.

Real Madrid will pay 6.5 million euros for the player, with 80% going to SaoPaulo, 15% to his agent Julio Fressato and 5% to another unnamed representative, Uol reported.

Casemiro has been capped five times for Brazil since making his international debut under Mano Menezes in 2011.