Simplify the following text for a Grade 5 native English-speaking person.
Original: Sergio RodrÃ guez GarcÃ a , aka Rodri ( born 17 August 1984 in MatarÃ , Barcelona , Catalonia ) , is a Spanish footballer who plays for FC Spartak Moscow , mainly as a central defender .
Simplified: Sergio RodrÃ guez GarcÃ a ( born 17 August 1984 ) is a Spanish football player .