The NBA has officially approved a couple of new rules for the 2019-20 season, which includes giving coaches the ability to challenge certain calls on the floor. The league has experimented with coach's challenges during the 2019 Summer League, a system which has already been tested out in the G League over the last two seasons. 

The decision was approved following a formal vote of the board of governors on Tuesday.

In order to challenge a play, coaches must have a timeout remaining, and the team must call a timeout immediately after the incident they wish to challenge takes place. Tim Reynolds of the Associated Press (H/T NBA.com) reports:

"As with other replay reviews, in order to overturn the event as called on the floor, there must be clear and conclusive visual evidence that the call was incorrect," NBA Basketball Operations President Byron Spruell told teams in a memo.

Unlike the NFL version of a challenge, there's no flag to be used and teams will not retain them even if successful. A team will have to call timeout and the coach "must immediately signal for a challenge by twirling his/her index finger toward the referees," the memo said.

According to ESPN's Zach Lowe, a league memo regarding the coach's challenges states:

"Coaches will get one challenge per game, and they will lose it even if the challenge is successful, according to the memo. They can use it to challenge only called fouls, goaltending, basket interference, and plays when the ball is knocked out of bounds, the memo says."

Additionally, the league approved a new rule that will allow the replay center in Secaucus, New Jersey to trigger instant replay on select plays.