Ryan Nagelhout 
Football: Who Does What? [PDF ebook] 

The game of football has many rules, and each position on the field is different. Whether lining up in the trenches to protect the quarterback or running the ball out of the backfield, the 11 players on each team each have special jobs to do. This book gives readers a look at each position on the gridiron, showing how cornerbacks and safeties cover wide receivers and how linebackers try to sack the quarterback. With a detailed look at each position, readers will be ready to take the field themselves and play America’s most popular game with their friends.