The portion of an offensive formation that lines up behind the offensive line and between the tackles. The offensive backfield usually consists of the quarterback and a variety of running backs. In specific formations, another player may line up in the offensive backfield. The alignment of players in the backfield tends to provide hints about the type of play the offense is likely to run.
The offensive backfield changes with each formation that the offense runs. The quarterback will be joined in the backfield by running backs, tight ends, wide receivers, or other players depending on what play the offense is running. The arrangement of these players is often indicative of what the offense is going to run. Offensive backfields with multiple running backs tend to lean towards running plays, while a backfield with just the quarterback or a single running back are passing heavy. Backfields will often shift before a play to gain an advantage just prior to the snap.