Lewis, vibraphonist Milt Jackson, drummer Clarke and bassist Ray Brown had been the small group within the Gillespie big band, and they frequently played their own short sets when the brass and reeds needed a break or even when Gillespie's band was not playing. The small band received a lot of positive recognition and it led to the foursome forming a full-time working group, which they initially called the Milt Jackson Quartet in 1951 but in 1952 renamed the Modern Jazz Quartet.