At the back of each end zone are two ‘goal posts’ (also called ‘uprights’) that
are 18.5 feet apart. The posts are connected by a crossbar 10 feet from the
ground. Successful kicks must go above the crossbar and between the uprights.
Each team has 11 players on the field at a time. However, teams may substitute
for any or all of their players, if time allows, during the break between plays.
As a result, players have very specialized roles, and almost all of the players
on any team will play in any given game. Thus, teams are divided into three
separate units: the offence, the defence and the special teams.
A standard football game consists of four 15-minute periods (called quarters),
with an intermission (called halftime) after the second quarter. The clock stops
after certain plays (when a forward pass is dropped or the ball leaves or is
taken out of the field of play); therefore, a game can last considerably longer
(often more than three hours in real time).
The Offence
The offensive line (O-Line) consists
of five players whose job is to protect the passer and clear the way for runners
by blocking members of the defence. Except for the centre, offensive linemen
generally do not handle the ball.
The quarterback (QBs) receives the
ball on most plays. He then hands or tosses it to a running back, throws it to a
receiver or runs with it himself.
Running backs
(RBs) line up behind or beside the QB and specialize in rushing with the ball.
They also block, catch passes and, on rare occasions, pass the ball to others.
Wide receivers
(WRs) line up near the sidelines. They specialize in catching passes.
Tight ends (TEs)
line up outside the offensive line. They can either play like wide receivers
(try to catch passes) or like offensive linemen (protect the QB or create spaces
for runners).
Not all of these types of players will be
in on every offensive play. Teams can vary the number of wide receivers, tight
ends and running backs on the field at one time.
The Defence
The defensive line (D-Line) consists
of three to five players who line up across from the offensive line. They try to
tackle the running backs before they can gain yardage or the quarterback before
he can throw a pass.
At least three players line up as
defensive backs (DBs). They cover the receivers and try to stop
pass
completions and catch passes thrown by the QB. They occasionally rush the quarterback.
The other players on the defence are known
as linebackers (LBs). They line up between the defensive line and backs
and may either rush the quarterback or cover potential receivers.
Special Teams
The units of players who handle kicking
plays are known as special teams. Two important special-teams players are
the punter, who handles punts, and the placekicker or kicker,
who kicks off and attempts field goals and extra points. It is rare, but not
unheard of, for these two positions to be filled by the same player.
Advancing the ball
Advancing the ball in American football
resembles the six-tackle in rugby league football. The team that takes
possession of the ball (the offence) has four attempts, called downs, to
advance the ball 10 yards towards their opponent's (the defence's) end zone.
When the offence gains 10 yards, it gets a first down, or another set of four
downs to gain 10 yards. If the offence fails to gain a first down (10 yards)
after 4 downs, it loses possession of the ball.
Except at the beginning of halves and after
scores, the ball is always put into play by a snap. All players line up
facing each other at the line of scrimmage (the position on the field
where the play begins). One offensive player, the centre, then passes (or
"snaps") the ball between his legs to a team-mate, usually the
quarterback.
Players can then advance the ball in two
ways:
By running with the ball, also known as
rushing.
By throwing the ball to a team-mate, known
as passing. The forward pass is a key factor distinguishing American and
Canadian football from other football sports. The offense can throw the ball
forward only once on a play and only from behind the line of scrimmage. The ball
can be thrown sideways or backwards at any time. This type of pass is known as a
lateral and is much rarer in American football than in rugby league or
rugby union.
A play or down ends, and the ball becomes
dead, after any of the following:
The player with the ball is forced to the
ground or has his forward progress halted by members of the other team (as
determined by an official).
A forward pass flies out of bounds or
touches the ground before it is caught. This is known as an incomplete pass.
The ball is returned to the original line of scrimmage for the next down.
The ball or the player with the ball goes
beyond the dimensions of the field (out of bounds).
A team scores.
Officials blow a whistle to notify
all players that the play is over.
At all times, players must be aware of the
sequence of downs and the distance to a new first down. If the team gains three
yards on the first play, for example, the next down will be "2nd and 7." If a
team gains a first down within the ten yard line then the scoreboard or
television reads "(the down) and goal."
Changes of possession
The offence maintains possession of the
ball unless one of the following things happens:
The team fails to get a first down, that
is, move the ball forward at least 10 yards in four downs. The defensive team
takes over the ball at the spot where the play ends. A change of possession in
this manner is commonly called a ‘turnover on downs’.
The offense scores a touchdown or field
goal. The team that scored then kicks off the ball to the other team.
The offense punts the ball to the defence.
A punt is a kick in which a player drops the ball and kicks it before it
hits the ground. Punts are nearly always made on fourth down, when the offensive
team does not want to risk giving up the ball to the other team at its current
spot on the field (through a failed attempt to make a first down) and feels it
is too far from the other team's goal posts to kick a field goal.
A defensive player catches a forward pass
to a receiver. This is called an interception, and the player who makes
the interception can run with the ball until tackled, forced out of bounds, or
scores. After the intercepting player is tackled or forced out of bounds, his
team's offensive unit returns to the field and takes over at his last position.
An offensive player drops the ball (a
fumble) and a defensive player picks it up. As with interceptions, a player
recovering a fumble can run with the ball until tackled or forced out of bounds.
Lost fumbles and interceptions are together known as turnovers.
The offensive team misses a field goal
attempt. The defensive team gets the ball at the spot where the previous play
began.
An offensive ball carrier is tackled,
forced out of bounds, loses the ball out of bounds, or commits certain penalties
in his own end zone. This rare occurrence is called a safety.
Back to top
Scoring
A team scores points by the following
plays:
A touchdown (TD) is worth 6 points.
A touchdown is scored when a player runs the ball into or catches a pass in his
opponent's end zone.
After a touchdown, the scoring team
attempts a conversion. The ball is placed at the other team's 3-yard line. The
team can attempt to kick it over the crossbar and through the goal posts in the
manner of a field goal for 1 point (an extra point or point after
touchdown (PAT)), or run or pass it into the end zone in the manner of a
touchdown for 2 points (a two-point conversion).
A field goal (FG) is worth 3 points,
and it is scored by kicking the ball over the crossbar and through the goal
posts. Field goals must be placekicked (kicked when the ball is held vertically
against the ground by a team-mate.
A safety is worth 2 points. A safety
is scored by the defence when the offensive player in possession of the ball is
forced back into his own end zone and is tackled there, or fumbles the ball out
of the end zone. Certain penalties by the offense occurring in the end zone also
result in a safety - these result in two points.
Kick-offs and free kicks
Each half begins with a kick-off.
Teams also kick off after scoring touchdowns and field goals. The ball is kicked
from a kicking tee, which is made from one's own 35-yard line. The other team's
‘kick returner’ tries to catch the ball and advance it as far as possible. Where
he is stopped is the point where the offense will begin its drive, or series of
offensive plays. If a kick returner does not want to run with the ball, he has
the option to signal for a "fair catch" by waving his hands in the air before
the catch. He will then be allowed to catch the ball without being tackled. If
the kick returner catches the ball in his own end zone, he can either run with
the ball, or elect for a touchback by kneeling in the end zone.
The receiving team can then start its offensive drive from its own 20-yard line.
A touchback also occurs when the kick goes out of the end zone. Punts and
turnovers in the end zone can also end in touchbacks.
After safeties, the team that gave up the 2
points puts the ball into play with a punt or placekick from its own 20-yard
line.
Penalties
Rule
violations are punished with penalties. Most penalties result in moving
the football either towards the endzone in the case of a defensive penalty, or
away from the endzone in the case of an offensive penalty. Some defensive
penalties give the offense an automatic first down. In addition, if a penalty
gives the offensive team enough yardage to gain a first down, the first down is
automatically given. If a penalty occurs during a play, an official throws a
yellow flag near the spot of the foul. When the play is over, the team that did
not commit the penalty has the option of taking either the penalty or
the result
of the play. For example, say a defensive player commits an offsides penalty on
first down by passing the line of scrimmage before the snap, and the offense
gains eight yards on the play. The team with the ball has the option of taking
the penalty and repeat the first down with five yards to go, or declining the
penalty and scrimmaging with 2nd and 2.
(Penalty shown here is known as
'Facemasking'- No player is allowed to take hold of another player's face cage)
