LA Rams: Safety Jordan Fuller is wearing the green dot

Two for one rule

And so, radio communications entered the football field. That innovation had a hand in changing the game even more because quarterbacks who had historically called their own plays became slowly replaced by quarterbacks who merely executed the plays called in from the sidelines. No more drawing up plays in the dirt in the huddle. Now, most NFL quarterbacks are limited to an option to audible or change the preset play at the line of scrimmage by hollering out the audible signal during the snap count.

But the NFL didn’t want the game to change too dramatically, too quickly. So the league installed a new set of rules for helmet-communication technology.

From 1994 to 2008, only quarterbacks were allowed to do so. That changed in 2008, when the league allowed defenses to get in on the communications action, as well.

There’s actually the ability for a team to have three players designated to wear the green dot – one on offense (usually the QB, and Matthew Stafford will likely get the green dot for the offense and (usually) two players on the defensive side of the ball (because defensive players are situational and might not be on the field for all downs).

The NFL rules allow for two defensive players to possess “live” helmets (ones equipped with microphones and headsets) due to the situational role of sub-packages, but only one live helmet can be on the field at a time.  Since many defenses will replace an interior linebacker for a defensive back, the NFL allowed that transition by authorizing the second helmet in the case where a primary signal-caller is swapped off the field.

Fuller receiving a green dot means that the LA Rams have an option to designate another green dot on defense.