How the NBA's New Instant Replay Rule Works, Explained

On Tuesday, the NBA Board of Governors approved an expanded use of the Coach's Challenge that will take effect starting in the 2024-25 season. Here's what you need to know about the change.

A Wilson official NBA game ball on the court at Crypto.com Arena. / Kirby Lee-Imagn Images

The NBA Board of Governors approved an expanded use of the Coach's Challenge when reviewing out-of-bounds violations, the NBA league office announced on Tuesday.

Under the new ruling, if instant replay is triggered by a Coach's Challenge, the on-court officials and Replay Center will then be able to review video of the play and determine whether a foul should have been called proximate to the violation.

In short, a Coach's Challenge for a review of an out-of-bounds call can now result in a previously missed or uncalled foul being assessed.

How It Works

The NBA office provided an example of how the new rule will work, utilizing a call that was challenged during the most recent Western Conference Finals between the Dallas Mavericks and Minnesota Timberwolves.

Upon review, video shows that Mavericks guard Kyrie Irving made contact with McDaniels' arm, knocking the ball from McDaniels' hands. The Replay Center determined the ball was last touched by McDaniels and overturned the call, deeming Dallas' challenge successful and awarding the Mavericks possession.

In the play (see here), Dallas challenged the ruling on the floor, which originally rewarded Minnesota with possession after an out-of-bounds play. Officials initially believed that Dallas knocked the ball out of Timberwolves forward Jaden McDaniels' hands, and Mavericks head coach Jason Kidd initiated a Coach's Challenge.

Under the new ruling, the Mavericks' challenge would be ruled unsuccessful and a personal foul would be assessed to Irving, citing the illegal contact that knocked the ball free from McDaniels' hands. Minnesota would either retain possession or shoot free throws if the Timberwolves were in the bonus.

Irving's foul would be considered proximate to the out-of-bounds violation being reviewed.

Dallas Mavericks guard Luka Doncic (77) pleads to the official during the third quarter against the Minnesota Timberwolves in game four of the western conference finals for the 2024 NBA playoffs at American Airlines Center. / Jerome Miron-Imagn Images

Three factors will be considered in determining whether a prior uncalled foul is proximate to the out-of-bounds violation, according to the release:

• Whether the players involved in the uncalled foul are the same or different than the ones involved in the out-of-bounds violation under review
• The distance between the uncalled foul and the out-of-bounds violation under review
• The time elapsed between the uncalled foul and the out-of-bounds violation

While this implementation means replay reviews could take longer and slow down a game, it also means the NBA is taking more steps, hoping to eliminate missed foul calls in key moments of games.

The change goes into effect beginning with the upcoming 2024-25 NBA season, which begins with preseason on October 4 and the regular season on October 22.

The NBA's competition committee unanimously recommended the rule change to the NBA's Board of Governors. The Competition Committee consists of players, representatives from the NBPA, coaches, governors, team and league basketball executives and referees.