Rock and roll first entered mainstream popular music through a style called "rockabilly", which fused the nascent rock sound with elements of country music. Black-performed rock and roll previously had limited mainstream success, and some observers at the time believed that a white performer who could credibly sing in an R&B and country style would be a success. Sam Phillips, of Memphis, Tennessee's Sun Records, found such a performer in Elvis Presley, who became one of the best-selling musicians in history, and brought rock and roll to audiences across the world. Presley's success was preceded by Bill Haley, a white performer whose "Rock Around the Clock" is sometimes pointed to as the start of the rock era. However, Haley's music was "more arranged" and "more calculated" than the "looser rhythms" of rockabilly, which also, unlike Haley, did not use saxophones or chorus singing.