For 1878 the Century League returned the same six clubs it had the previous year. The results however, could not have been different. Embarrassed and angry after a dismal season in 1877, Miles Bigsby opened his wallet and remade his Brooklyn Unions. And it worked.

The new-look Unions turned it around completely, dominating the league to the tune of a 48-13 record and a fifteen-game margin over second-place Chicago (33-28). The Union Club had unearthed not one, but two stellar 21-year-old rookie pitchers in Buster Scott (25-8, 1.23) and Jim Cannon (23-5, 1.57). The offense was top-notch as well, finishing atop the circuit in runs scored (396), batting average (.300) and virtually every other category. Another rookie, 24-year-old Canadian outfielder Bob DeVilbiss left his Toronto club for Brooklyn and posted a .390 average (tops in the league) while also leading the league in runs scored, RBIs, home runs and pretty much every advanced stat (once the historians got around to working this out a hundred-plus years later).

DeVilbiss was supported by fellow rookie 3B Scott Wilkes (.336) and Detroit import Leonard Ziegler (who was sold to Brooklyn in the offseason by the cash-strapped Woodwards) who hit .335 a year after leading the league with Detroit. Every regular in the lineup hit over .300 with the sole exception of shortstop Lloyd Brumback. It was the most dominating performance in the three-season history of the Century League.

Brooklyn's dominance overshadowed everything else, including a fine season by 1877 champion Chicago. Whitney's men had good pitching with Will Ryan and Henry Walsh, both of whom were sub-2.00 in ERA, but the offense sputtered, finishing without a single .300 hitter and ended up last in the league in runs scored. Third-place went to Philadelphia who finished at 31-31. New York was just behind at 30-31. The also-rans were Boston (20-40) and last-place Detroit (22-41), which was suffering through financial difficulties.

Off the field, CL President Whitney spent much of his summer trying to find replacement clubs to get his circuit back to the eight he believed was the ideal membership level. Ironically, he found them amongst the ranks of the independent and relatively informal barnstorming group that Cincinnati and St. Louis had joined.