ootball was — and is — a very dynamic game, especially in the aspect of the rules of the game. Rules revisions have been a dominant feature of the game since the late 1800s and are still prevalent. The year 1921 was no exception to that trend, and that season featured rules revisions that still have some force in today’s contests.

The last edition of this series discussed a few of the changes in 1921: Players were "urged" to wear numbers on their jerseys, and they even explored views on cleats and helmets. This part of our study on football rules history will really hone in on the balance of rules revision from 1921.