Each team has eleven players on the field at once. The trick that trips up newcomers is that the eleven who attack are entirely different people from the eleven who defend, and they swap on and off as the ball changes hands. So when you watch, you are really watching two separate teams take turns. Here is who does what, side by side.
A quick word on one term, because it catches out UK readers. The offense (the team with the ball, trying to score) and the defense (the team trying to stop them). If you spell that word with a c at home, defence, you will see it with an s here, because that is how the sport spells it.
Here are the groups at a glance, and then I will go through each:
| Side | The positions |
|---|---|
| Offense (has the ball) | Quarterback, running back, wide receivers, tight end, offensive line |
| Defense (stops them) | Defensive line, linebackers, defensive backs |
| Special teams | Kicker, punter, long snapper, returner |
The offense: who has the ball
The quarterback is the one you already know, even if you did not realise it. He takes the ball at the start of every play and decides what happens: hand it to a runner, throw it to a receiver, or keep it and run. He directs the whole thing, and the team is built around him.
The running back takes handoffs and runs with the ball, and often catches short passes too. The wide receivers are the fast players who sprint downfield to catch throws. The tight end is the useful hybrid: he lines up near the big blockers, and he both blocks and catches, which makes him hard to plan for.
And then there is the offensive line: five players whose entire job is to block. They protect the quarterback and clear paths for the runner. They are not allowed to catch the ball, and they almost never touch it. Which brings me to the most undervalued thing in the sport.
The offensive line: winning games without the ball
Here is the reframe that changes how you watch. Everyone follows the quarterback and the ball. But games are won and lost by the five linemen who never touch it.
The rulebook itself sets them apart. An offensive formation must have “seven or more players on the line”, and the players in the middle of that line are not allowed to catch a forward pass. That is the whole reason offensive linemen wear numbers between 50 and 79: the number is a signal to the officials that this player is ineligible to catch the ball. Their job is not to score. It is to make sure everyone else can.
Teams know exactly how much this matters, even when fans do not. The left tackle, who guards the blind side of a right-handed quarterback (the side he cannot see when he sets up to throw), is the highest-paid position in the sport after quarterback itself. Clubs spend enormous sums on a player whose job is to stop bad things happening to someone else.
And yet the credit never follows the money. No offensive lineman has ever been named the league’s Most Valuable Player, and the last non-quarterback of any kind to win it was a running back, back in 2012. The men who make an offense work are the ones nobody names on the walk home. Start watching the line instead of the ball, and you are watching a different, better game.
The defence: who stops them
Facing the offense is the defence, also eleven players, in three layers.
The defensive line are the big players right at the front, trying to tackle the runner and to sack the quarterback (bring him down before he can throw). Behind them, the linebackers are the do-everything players: they stop runs, chase down passes, and sometimes charge the quarterback themselves. At the back are the defensive backs, the fast players who cover the receivers and knock away or intercept throws. These are the cornerbacks and the safeties.
That word again: a safety here is a defensive player, the last line of defence at the very back. It is the same word as the two-point score from the scoring page, which is a genuine coincidence of naming that trips up everyone. Position, not points, when it is a person.
Special teams
There is a third unit you will see for kicks and punts: special teams. It has its own specialists, the kicker and the punter, plus a long snapper who hikes the ball back to them and a returner who fields kicks and runs them back. They are on the field only for the kicking plays, but those plays swing field position and points, so they matter more than their few appearances suggest.
Common questions
How many players are on the field in American football?
Eleven from each team, so twenty-two in total. But the eleven on attack (the offense) are different players from the eleven who defend, and they swap on and off as the ball changes hands. So a squad carries far more than twenty-two players, each specialising in one side of the ball.
What are the positions in American football?
On offense: the quarterback, who runs the play; running backs and wide receivers, who carry and catch the ball; a tight end, who does both; and five offensive linemen, who block. On defense: the defensive line, linebackers, and defensive backs, who stop them. Plus special teams for kicking.
What does a quarterback do?
The quarterback takes the ball at the start of each play and decides what happens with it: hand it to a runner, throw it to a receiver, or run himself. He is the player who directs the offense and the one the whole team is built around, which is why he gets the most attention.
Where to go next
- NFL Rules Decoded: how the whole game works.
- Scoring Decoded: what all these players are trying to do.
- Penalties & Pass Interference Decoded: the fouls these positions get called for.
Want it straight from the source? The formation and eligible-receiver rules are in the NFL’s official rulebook, and the league’s Video Rulebook shows them with clips.