Casemiro has joined Real Madrid on loan from Sao Paulo until the end of the season, with an option to make the move permanent.
The midfielder, who has been with the Brazilian club since the age of 11, will start at the Spanish giants' B side Real Madris Castilla.
The 20-year-old has made over 60 appearances for his home club in three years in the first team.
Casemiro's agent Joseph Lee explained to Lancenet: "It's loan deal until the end of the season, with an option to buy.
"It's not that he will play for the B team, he will just acclimatise in the B team, and then will play for the A team later on.
"This is something he needs, but the offer comes for him to play for the senior team, he is not a B team player.
"He was not playing at Sao Paulo and he needs to play. The offer came, we talked with Casemiro who expressed his interest."