Line of Scrimmage
The line of scrimmage is also known as the scrimmage line.
Football Blue Line
REMEMBER: The scrimmage line will always show the spot of the ball on the field!
Football Chain Crew
The chain crew is a group of referees responsible for marking the line of scrimmage after every down. They are called the chain crew because they carry a massive to chain to measure the exact location of the ball on the field.