Rafael has signed a four-year contract at Manchester United which will keep the full-back at the club until the end of the 2015/16 season.
The 21-year-old arrived at Old Trafford along with his twin brother Fabio from Fluminense in 2008, and his performances for the first team have warranted a call-up to the Brazil squad.
Rafael expressed his delight at securing his future, telling the club s website: I am so happy to sign a new contract.
I love playing for Manchester United. There is a great team spirit here and a real desire to win.
My time here has been unbelievable winning two league titles, a league cup and a Club World Cup has made me hungry for more trophies.
I would like to thank Sir Alex for his belief in me and I would also like to thank the fans for their support.