Scrimmage vests (also known as pinnies or training bibs) are lightweight, often brightly colored jerseys used in sports practices and scrimmages to help visually distinguish players or teams. Here’s a breakdown of their purpose:

Primary Uses:

1. Team Identification:
   During practices or informal games, players on the same team may not wear matching uniforms. Vests help quickly identify who's on which side.

2. Positional Roles:
   In training, coaches may assign different colors to indicate specific roles — like defenders in yellow, midfielders in blue, etc.

3. Organization & Clarity:
   Keeps practice drills structured, reducing confusion when players are mixing in a shared field or space.

4. Substitute Marking:
   In games, substitutes may wear scrimmage vests over their jerseys while on the bench to avoid confusing officials and players.