king was repeatedly rejected in auditions for the south side's chess records, the premier blues label, which was the home of muddy waters, howlin' wolf, and little walter. the complaint was that king sang too much like b.b. king. a newer blues scene, lively with nightclubs and upstart record companies, was burgeoning on the west side, though. the bassist and producer willie dixon, during a period of estrangement from chess in the late 1950s, asked king to come to cobra records for a session, but the results have never been heard. meanwhile, king established himself as perhaps the biggest musical force on the west side. he played along with magic sam and reputedly played backing guitar, uncredited, on some of sam's tracks for mel london's chief and age labels, though king does not stand out on them.