From Blaseball Wiki

Cycling is a Ballpark renovation introduced in the Semi-Centennial that causes the pitchers to rotate at the start of every inning.


Cycling was first seen in the ILB Semi-Centennial as one of the renovations for the ILB Historical Preservation Site, the stadium of the Vault Legends. Cycling was used to ensure that the many pitchers of both teams were able to play during the 50 inning Semi-Centennial match.