Only 11 seasons since 1901 have featured both the Chicago Cubs and Chicago White Sox in contention as of Aug. 17, according to data drawn from Baseball Reference. That span covers 126 seasons commonly considered the modern era, meaning both clubs were within the author’s defined contention threshold in just 9% of seasons.
The author used Aug. 17 snapshots for each year back to 1901, consulting Baseball Reference’s archived win‑loss records, games back, pennant chances and playoff odds. A cutoff of five games behind or fewer from a playoff slot was used to flag a contender at that date.
Using those criteria, there were 29 seasons (23%) in which the White Sox were contending while the Cubs were not, and 32 seasons (25%) in which the Cubs were contending but the White Sox were not. In 54 seasons (43%), neither club was within the five‑game threshold as of Aug. 17.
Both teams have reached the postseason in the same year just three times: 1906, 2008 and 2020, the latter being a shortened season. The 1906 season is the only year on record in which both clubs held first place on Aug. 17; both clubs also finished in first place in 2008. There have been three instances of consecutive seasons with dual contention: 1906–1907, 2003–2004 and 2008–2009, the historical review shows.
The writer also tracked recent simulations of season outcomes. Those daily season simulations produced odds of roughly 63‑to‑1 that the Cubs and White Sox would meet in the World Series at the time the teams were set to open a mid‑August series, according to the author’s log of the simulation results. By contrast, the furthest combined distance from contention on record came in 1942, when the Cubs were 28½ games out on Aug. 17, per the Baseball Reference data.
