Simplify the following text for a Grade 7 native English-speaking person.
Original: Juan Silveira dos Santos ( ; born 1 February 1979 in Rio de Janeiro ) , commonly known as Juan or Juan The Beast , is a Brazilian footballer who currently plays as a central defender for Italian side Roma and the Brazilian national team .
Simplified: Juan Silveira dos Santos ( born 1 February 1979 ) is a Brazilian football player .