Willie Mays Signed Autographed Giamatti Era Official Rawlings Baseball JSA LOAWillie Mays Signed Autographed Giamatti Era Official Rawlings Baseball JSA LOA Mays was an American professional baseball player who played 23 seasons in Major League Baseball Widely regarded as one of the greatest players of all time, Mays began his career in the Negro leagues, playing for the Birmingham Black Barons, and spent the rest of his career in the National League (NL), playing for the New York San Francisco Giants and New York Mets. Willie