On July 18, 1953, , Presley went to Sun Records' Memphis Recording Service to record "My Happiness" with "That's When Your Heartaches Begin", supposedly a present for his mother. On January 4, 1954, he cut a second acetate. Sun Records boss Sam Phillips was on the lookout for someone who could deliver a blend of black blues and boogie-woogie music; he thought it would be very popular among white people. Assistant Marion Keisker called Presley on June 26, 1954. After an inauspicious session, Phillips invited local musicians Winfield "Scotty" Moore and Bill Black to audition Presley. Though not overly impressed, a studio session was planned.
During a recording break, Presley began "acting the fool" first with Arthur Crudup's "That's All Right (Mama)". Phillips got them all to restart and began taping. This was the sound he had been looking for. The group recorded other songs, including Bill Monroe's "Blue Moon of Kentucky". "That's All Right" was aired on July 8, 1954, by DJ Dewey Phillips. After its release, both sides of "That's All Right"/"Blue Moon of Kentucky" began to chart across the South.
Moore and Black began playing regularly with Presley. They gave a few performances in July 1954 to promote the Sun single at the Bon Air, a rowdy music club where the band was not well-received. On July 30 the trio, billed as The Blue Moon Boys, made their first appearance at the Overton Park Shell, with Slim Whitman headlining. A nervous Presley's legs were said to have shaken uncontrollably during this show: his wide-legged pants emphasized his leg movements, apparently causing females in the audience to go "crazy". Presley consciously incorporated similar movements into future shows.
DJ and promoter Bob Neal became the trio's manager (replacing Scotty Moore). Moore and Black left their band, the Starlite Wranglers and, from August through October 1954, appeared with Presley at The Eagle's Nest. Presley debuted at the Grand Ole Opry in Nashville on October 2; Hank Snow introduced Presley on stage. He performed "Blue Moon of Kentucky" but received only a polite response. Afterwards, the singer was allegedly told: "Boy, you’d better keep driving that truck."
Country music promoter and manager Tillman Franks booked Presley for the Louisiana Hayride on October 16. Before Franks saw Presley, he referred to him as "that new black singer with the funny name". During Presley's first set, the reaction was muted; for the second, Franks advised Presley to "Let it all go!" As house drummer D.J. Fontana (who had worked in strip clubs) complemented Presley's movements with accented beats and Bill Black engaged in his usual stage antics, the crowd was more responsive. According to one source, "Audiences had never before heard [such] music... [or] seen anyone who performed like Presley either. The shy, polite, mumbling boy gained self-confidence with every appearance... People watching the show were astounded and shocked, both by the ferocity of his performance, and the crowd’s reaction to it... Roy Orbison saw Presley for the first time in Odessa, Texas: 'His energy was incredible, his instinct was just amazing... I just didn’t know what to make of it. There was just no reference point in the culture to compare it.'"Sam Phillips said Presley "put every ounce of emotion ... into every song, almost as if he was incapable of holding back."