Only two offenses lined up in 21 personnel on first down more than 30 percent of the time last season — the San Francisco 49ers and Miami Dolphins.
Five teams didn’t take a first-down snap with two running backs on the field and 22 teams leveraged 21 personnel on less than 10 percent of first-down plays. The value of a running back is under the microscope as players struggle to secure long-term deals, but coaches Mike McDaniel and Kyle Shanahan have players that drastically change the equation.