Complex sentence: He helped establish Philadelphia as a major hub of the Negro league baseball and, along with Jacob C. White, Jr., ran the Pythian Baseball Club (Silcox 1977: 66--67).
Split into simpler sentences: He helped establish Philadelphia as a major hub of Negro league baseball. Along with Jacob C. White, Jr. he ran the Pythian Baseball Club of Philidelphia (Silcox 1977: 66--67).