Slotback

Slotback, sometimes referred to as an A-back or, especially in the United States, slot receiver, is a position in gridiron football. The "slot" is the area between the last offensive lineman on either side of the center and the wide receiver on that side. A player who lines up between those two players and behind the line of scrimmage is a slotback. The position is a fixture of Canadian football and indoor football, but is also used in American football. The slotback is similar to the wide receiver but also has many of the same traits as a running back or tight end; a slotback lines up closer to the offensive line and often farther back than a wide receiver.

Slotbacks are often as many as five yards behind the line of scrimmage when the ball is snapped and, in the Canadian and indoor game, may also make a running start toward the line of scrimmage prior to the snap. In most forms of American football, this would be an illegal motion, although a few professional leagues such as the World Football League and XFL allowed forward motion.

Duties of the slotback
There are a number of different jobs a slotback may take up on the field. Primarily, they are used as hybrid running backs/receivers. However, they are often used to block any player on the defensive team who breaks through the line of scrimmage as a precaution to prevent the sacking of the quarterback. They are preferred over the wide receiver or tight end for receiving short passes or handoffs due to their positioning being closer to the quarterback. When formations containing slotbacks are used in American football the team often has to go without a tight end, a fullback or a running back due to there being only 11 men on the offense and 7 being on the line of scrimmage, one reason they are rarer in the American game. However, as NFL teams have increasingly "defaulted to three- and four-receiver sets" in recent years, the slot receiver has become a fixture of American football formations. In terms of a depth chart, a slotback is typically considered the third wide receiver and may be expected to be a "possession receiver" that can reliably catch a pass when covered by a safety, since they are most commonly used when converting medium-distance third-down conversions.

Slotbacks are used effectively in flexbone formations, in which they are used as extra receivers.
Slotbacks are usually smaller and faster than the other positions used. they are also used for short passes and short runs to get extra yards or a first down or a third down drive.

See also
H-back, a similar position
Slotback can also mean a running back, just a similar name for it.
Slotback are there to serve the quarterback and wide receivers for passes and yards, some plays are meant for the slotbacks and no other positions on the field.
If a team wanted to use a slotback, they have to have a tight end on the edge by the tackle and has to be on the line. on the depth charts, slotbacks are labeled as wide receivers. 
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Category:American football positions
Category:Canadian football terminology