Glossary of American Football - U

U

unbalanced line
Usually refers to an offensive formation which does not have an equal number of linemen on each side of the ball. Done to gain a blocking advantage on one side of the formation; typically one tackle or guard lines up on the other side of the ball. For example a common alignment would be E-G-C-G-T-T-E.
under center
Refers to the quarterback lining up directly behind the center to take the snap. The person under center is conisdered ineligible in the NFL, but an eligible receiver in the NCAA and high school, though this distinction rarely manifests itself since the person under center usually is the passer. Contrast with shotgun formation.
undrafted
A player who enters the NFL Draft but is not selected by any team in the draft's seven rounds. Undrafted players are free agents and can sign with whatever team they so choose if that team is willing to take them.
upback
A player, in a scrimmage kick (punts and field goals) or kneel formations, who lines up behind the offensive line. An upback's primary duty is to block oncoming defensive players in a kick formation and to recover any fumbles in a kneel formation. They can receive direct snaps, and upbacks are eligible receivers.
upman
During a kickoff, every player on the return team is called an "upman" with the exception of the one or two designated kickoff returners, who stand furthest away from the starting point of the kicking team.
utility player
A player capable of playing multiple positions

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