Robert Trujillo
Robert Trujillo ( , ; born October 23 , 1964 ) is an American musician and songwriter , best known for being the bassist of heavy metal band Metallica since 2003 . 
<triplet> Robert Trujillo <subj> October 23, 1964 <obj> date of birth <subj> Metallica <obj> member of <triplet> Metallica <subj> Robert Trujillo <obj> has part <subj> heavy metal <obj> genre