Final answer:
The 'deal' Mr. Calloway offered his white clients after showing up to play refers to racial discrimination in the Jim Crow era.
Step-by-step explanation:
The 'deal' Mr. Calloway offered his white clients after showing up to play refers to the racial segregation and discrimination in the Jim Crow era. During this time, African American athletes were often subject to unfair treatment and exclusion from playing with white athletes. Mr. Calloway's 'deal' likely involved negotiating for his black players to be allowed to compete on an equal footing with their white counterparts.
Learn more about Jim Crow era