As of August 2025 , the Colorado Rockies have a run differential of -316 for the 2025 MLB season. Their 114 games are the fewest to reach a -300 run differential since 1900, surpassing the 1911 Boston Rustlers (118 games).The last team to reach the mark in fewer games was the 1899 Cleveland Spiders, who did so in 73 games before folding at the end of the season.

The Chicago White Sox struggled at a similar historical level throughout the full duration of the 2024 season. At the end of September, the White Sox broke the modern MLB era record for most losses in a season.

Check out the historical rundown below:

Worst Records, MLB History br/> (Min. 150 Games Played; W-L, Win Pct)

1899 Cleveland Spiders: 20-134, .130

1916 Philadelphia A's: 36-117, .235

1935 Boston Braves: 38-11

See Full Page