Presley made enough of an impression that Phillips deputized guitarist Scotty Moore, who then enlisted bassist Bill Black, both from the Starlight Wranglers, a local western swing band, to work with the green young Elvis. The trio rehearsed dozens of songs, from traditional country, to "Harbor Lights", a hit for crooner Bing Crosby to gospel. During a break on July 5, 1954, Elvis "jumped up ... and started frailin' guitar and singin' "That's All Right, Mama" (a 1946 blues song by Arthur "Big Boy" Crudup). Scotty and Bill began playing along. Excited, Phillips told them to "back up and start from the beginning." Two or three takes later, Phillips had a satisfactory recording, and released "That's All Right", on July 19, 1954, along with an "Elvis Presley Scotty and Bill" version of Bill Monroe's waltz, Blue Moon of Kentucky, a country standard.