Young attacker joins United after training with them for most of 2010.

D.C. United has signed 19-year-old Brazilian midfielder Junior Carriero, who had been training with the team for most of 2010.The attacking midfielder joined United as a guest player in March. He will be available for selection pending receipt of his International Transfer Certificate.“Junior is a young player who has shown to us that he has the potential to become a good professional,” said United General Manager Dave Kasper. “He has very good attacking qualities and can play a number of positions in midfielder. We look forward to getting him integrated into our team.”D.C. United fans might notice a resemblance to one of their former players, Fred, now with Philadelphia, and for good reason- Junior is his younger brother.For more on Major League Soccer, visit Goal.com's MLS page and join Goal.com USA's Facebook fan page