Dylan Murphy
The Basketball Dictionary
6 min readOct 16, 2017


Term: 2.9 (two-nine)

Definition: The number of seconds (2.9) a defender can occupy the paint without being an arm’s length away from an offensive player.

Synonyms: N/A

Explanation: According to the NBA rulebook (Rule No. 10, Section VII, parts b and d), defensive three seconds is defined as follows:

b. Any defensive player, who is positioned in the 16-foot lane or the area extending 4 feet past the lane endline, must be actively guarding an opponent within three seconds. Actively guarding means being within arms length of an offensive player and in a guarding position.

d. The defensive three-second count is suspended when: (1) a player is in the act of shooting, (2) there is a loss of team control, (3) the defender is actively guarding an opponent, (4) the defender completely clears the 16-foot lane or (5) it is imminent the defender will become legal.

Put simply, a defender cannot stand in the paint for three seconds without guarding anyone. Flip this on its head and you arrive at a contrasting inference, that a defender can occupy the paint for 2.9 seconds without guarding anyone — also known as two-nining. This single fact stands as the core principle of help defense and rim protection.

Better offensive players survey the floor continuously to identify potential driving lanes. Better help defenders man the center of the paint as a deterrent. If the offensive player sees bodies, he will be less likely to attack the traffic. This ability to prevent dribble-drives before they materialize is the most important part of two-nining. And even if they do occur, the two-nining player is better positioned to help.

How to Two-Nine

With only 2.9 seconds to work with, defenders cannot camp out. Offensive bigs, facing the same three-second rule, typically space the floor to the dunker spot — the area just outside the paint along the baseline. If a defender plants himself at the top of the restricted area, he is farther than an arm’s length away. As the third second approaches, he has to scamper out of the paint and back into position. Same goes for wing defenders guarding a man in the weak-side corner. He cannot venture so far over to the strong side that he is vulnerable to a skip pass.

These dangers shape the two main components of two-nining:

  1. Clear the paint on the weak side.
  2. Time up the two-nine appropriately.

The first rule is a function of practicality: Because most help comes from the weak side, it stands to reason that the man whom the helper guards is on the weak side as well. (Of course, there are situations where a offensive player sits in the strong-side dunker spot, warranting a clearance to the strong side. But this is less common, given that most offensive players create appropriate space to avoid such scenarios.)

The second rule is also one of common sense. Just because a defender has the right to occupy the paint for 2.9 seconds does not mean he should do so. Smarter offensive players capitalize when helpers slide out of the paint. With their momentum carrying them away from the strong side, defenders cannot recover in time to protect the rim. But when they are there, you’ll often hear backline defenders yelling “two-nine!” so his teammates know the help side is there.

Here’s an example of Glenn Robinson III of the Indiana Pacers heeding both rules against the Sacramento Kings. As Darren Collison of the Kings looks to attack a switch against Myles Turner, Robinson recognizes the immediate danger and two-nines. Straddling the paint, however, means Garrett Temple is free in the dunker spot. Robinson’s teammate C.J. Miles, therefore, appropriately sinks in to protect, leaving him with two players to watch: Temple and Anthony Tolliver.

Once Turner stops the initial burst, Collison takes a back dribble to reset his isolation. Even though Robinson has not been in the paint for the full 2.9 seconds, he correctly senses this moment to be an appropriate time for clearance. By the time Collison gears up again, he’ll have cleared and re-entered the paint. To be safe, however, he doesn’t completely drop back to Temple. He merely slides over and swipes for a touch — proving that he’s within arm’s length of his man, since he never actually leaves the paint. Had Temple been a step or two farther outside the paint, Robinson would have needed to get both feet outside the lane.

Collison settles for a jumper and Robinson doesn’t ever encounter the ball. This is the type of defense that never registers on the stat sheet. What appears to be a mismatch on paper is stymied by Robinson’s two-nine positioning and precise timing.

A further concern for two-nining players is the possibility of a quick lob. If the defender wanders outside the paint on the strong side, the offensive player in the opposite dunker is momentarily open before defenders can rotate. Against athletic bigs, this can result in an easy two points.

The touch clearance of the Robinson example is one of the most common tactics among bigs to remain in the paint for far longer than 2.9 seconds. Remember that, according to the rules, a player must be “within arm’s length of an offensive player” to negate defensive three seconds. The key word here is “an,” in that it does not specificy which offensive player. So as long as the defender touches an opponent every 2.9 seconds, he can hang out in the paint indefinitely.

Because a large portion of the off-ball action runs through the paint, defensive bigs have ample opportunity to reset the timer by tagging cutters. Take a look at Nikola Jokic of the Denver Nuggets doing just that below: He clogs the paint for 14 continuous seconds, never leaving until his team regains possession with six seconds left on the shot clock.

Mucking up the strong side and encouraging a long, arcing skip pass are core tenets of most NBA defenses. That’s why you’ll often hear NBA coaches yelling “load” (to the ball) or “shrink” (the defense) to their defenses throughout games: They want their team to compress the floor and put people between the ball-handler and the basket. Understanding how and when to execute this task, however, is a matter of two-nining properly.

If dribble penetration middle unlocks everything from an offensive perspective, its prevention marks the centerpiece of defense. Players earn public praise for their help defense by drawing charges or blocking shots, but two-nining is where the magic really happens. Teams that can cut the floor in half by constantly occupying the paint prevent all sorts of scoring opportunities from ever occuring.

Film Study: “Two-Nine”

Below is a video compilation of various examples of defenders two-nining. Remember to keep your eyes peeled on the weak side. Notice how defenders leap in and out of the paint in reaction to potential threats, and how bigs buy time in the paint by constantly touching opponents.



Dylan Murphy
The Basketball Dictionary

Previously: Atlanta Hawks D-League Scout, Fort Wayne Mad Ants Assistant Coach (NBA D-League). 2014 D-League Champion.