Morato has been a regular in Madrid's team this year and has scored 11 goals in 52 games for the side overall.

Italian champions Juventus confirmed the 21-year-old had signed a five-year deal worth 20 million euro ($27m) to be paid over three years which includes a buy-back clause.

The 22-year-old Casemiro played 25 games for Madrid in 2013-2014, but only started four of those.

Competition for Real midfield places is heating up with the arrival of German World Cup winner Toni Kroos this week.

The Real-Porto accord includes an option to buy. Porto have already bought Dutch defender Bruno Martins Indi this week and taken attacker Cristian Tello on a two-year loan from Barcelona.